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Sample records for long-term fertilizer effects

  1. Effect of long-term fertilization on soil nitrate distribution

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A thirteen years long-term field fertilizer experiment was conducted to monitor the effect of different fertilization on soil nitrate distribution. The results showed: (1) Applying relative excessive N fertilizer could result large quantities of NO3- residue and NO3- movement downward in soil profiles; amending phosphate fertilizer or organic manure with nitrogen fertilizer together could significantly improve the status of NO3- leaching downward due to the balanced uptake of nutrients by crops. (2) Appropriate amounts of nitrogen fertilizer which was equal or smaller than the optimal fertilization rate could not result in more NO3- leaching in Northern China. (3) Precipitation influenced the amounts and depth of soil NO3- leaching: NO3- could move to 80 cm depth or below at autumn or at the next spring when rainfall was higher during the rainy season through July to September in North China.

  2. Short- and long-term effects of unemployment on fertility.

    Science.gov (United States)

    Currie, Janet; Schwandt, Hannes

    2014-10-14

    Scholars have been examining the relationship between fertility and unemployment for more than a century. Most studies find that fertility falls with unemployment in the short run, but it is not known whether these negative effects persist, because women simply may postpone childbearing to better economic times. Using more than 140 million US birth records for the period 1975-2010, we analyze both the short- and long-run effects of unemployment on fertility. We follow fixed cohorts of US-born women defined by their own state and year of birth, and relate their fertility to the unemployment rate experienced by each cohort at different ages. We focus on conceptions that result in a live birth. We find that women in their early 20s are most affected by high unemployment rates in the short run and that the negative effects on fertility grow over time. A one percentage point increase in the average unemployment rate experienced between the ages of 20 and 24 reduces the short-run fertility of women in this age range by six conceptions per 1,000 women. When we follow these women to age 40, we find that a one percentage point increase in the unemployment rate experienced at ages 20-24 leads to an overall loss of 14.2 conceptions. This long-run effect is driven largely by women who remain childless and thus do not have either first births or higher-order births.

  3. The long-term effect of the timing of fertility decline on population size

    NARCIS (Netherlands)

    O'Neill, BC; Scherbov, S; Lutz, W

    1999-01-01

    Existing long-range population projections imply that the timing of the fertility transition has a relatively unimportant effect on long-term population size when compared with the impact of the level at which fertility is assumed eventually to stabilize. However, this note shows that the effect of

  4. The long-term effect of the timing of fertility decline on population size

    NARCIS (Netherlands)

    O'Neill, BC; Scherbov, S; Lutz, W

    1999-01-01

    Existing long-range population projections imply that the timing of the fertility transition has a relatively unimportant effect on long-term population size when compared with the impact of the level at which fertility is assumed eventually to stabilize. However, this note shows that the effect of

  5. Long-term organic fertilization effect on chernozem structure

    Science.gov (United States)

    Słowińska-Jurkiewicz, A.; Bryk, M.; Medvedev, V. V.

    2013-01-01

    The objective of the study was to examine the structure of typical Ukrainian chernozem developed on loess, which (I) had been fertilized by standard crop rotation since 1912 with farm yard manure at the rate of 16 t ha-1 and (II) had not been fertilized with farm yard manure by sugar beet monoculture since 1929. After harvest of winter wheat and sugar beet, the samples of undisturbed structure were taken from 5 layers of both profiles: 0-8, 10-18, 20-28, 30-38, and 40-48 cm. The morphological analysis of the structure of the investigated chernozem revealed that the most visible differences between the soil structures of the two pedons occurred in their superficial layers. The 0-18 cm layer of the soil in the experiment I had an aggregate structure, whereas analogous layer of the soil in experiment II was much more compacted. Below about 30 cm from the ground level both pedons had very similar structure. For the soil in the experiment I an appropriate crop rotation and regular supplies of organic matter allowed for preservation of a favourable structure even in the upper layers - in contrast to the soil in the experiment II.

  6. Effects of Long-term Located Fertilization on the Physico-chemical Property of Soil Humus

    Institute of Scientific and Technical Information of China (English)

    SHI Ji-ping; ZHANG Fu-dao; LIN Bao

    2002-01-01

    A systematic study concerning the effects of a long-term stationary fertilization on content and property of soil humus in fluvo-aquic soil sampled from Malan Farm, Xinji City, Hebei, and arid red soil and paddy red soil sampled from the Institute of Red Soil, Jinxian County, Jiangxi was conducted. The results showed that long-term fertilization had effects not only on the content and composition of soil humus, but also on the physico-chemical property of humus. With applying organic manure or combined application of organic manure and chemical fertilizer, E4 and E6 values of humic acid decreased in fluvo-aquic soil and arid red soil,but increased in paddy red soil. In paddy red soil, E4 and E6 values of humic acid increased also with a single application of chemical fertilizer, but E4 and E6 values had less change of humic acid in fluvo-aquic soil and arid red soil. The effects on the visible spectroscopic property of fulvic acid were different from that of humic acid. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase E4 and E6 values of fulvic acid in three types of soil. Single application of chemical fertilizer had less effect on the E4 and E6. Long-term fertilization could also influence the ultraviolet spectroscopic property of humus. With a single application of organic manure or combined application of organic manure and chemical fertilizer, the ultraviolet absorbance of humic acid and fulvic acid increased in the three types of soil.But this effect was obvious only in short wave length, and the effect could decrease if the wave length increased. With a single application of chemical fertilizer the ultraviolet absorbance of fulvic acid could increase, but it of humic acid increased only in fluvo-aquic soil. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase the content of total acidic groups, carboxy groups and

  7. Effect of Long-Term Fertilization on Soil Productivity and Nitrate Accumulation in Gansu Oasis

    Institute of Scientific and Technical Information of China (English)

    YANG Sheng-mao; LI Feng-min; SUO Dong-rang; GUO Tian-wen; WANG Jian-guo; SONG Bing-ling; JIN Shao-ling

    2006-01-01

    A long-term (1982-2001) field experiment was conducted in a calcareous soil under wheat (Triticum aestivum L.)-wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation system at Zhangye, Gansu Province, China to determine the effects of long-term fertilization on crop yield, nutrients interactions, content and accumulation of nitrate-N in soil profiles. Twentyfour plots in a split-plot factorial with a combination of eight treatments (from nitrogen (N), phosphorus (P), potassium (K) and farmyard manure (M) applications) and 3 replications were selected. Main treatments were M and without M, and the sub-treatments were no-fertilizer (CK), N, NP and NPK. When P and K fertilizers were part of treatments, their ratio to N was 1N:0.22P:0.42K. All M, P and K fertilizers were applied as the basal dressing. The grain yield was harvested each experimental period and straw yield for the period from 1988 to 1997. After crop harvest in 2000, the soil was sampled from the 0-20, 20-60, 60-100, 100-140 and 140-180 cm depths to determine NO3--N content. Maize yie ld of CK in 2000 was only 28.2% of that in 1984, and wheat in 2001 was 25.7% of that observed in 1982. Average impact of fertilizers on grain yield decreased in the order of N > M > P > K. Yield response to N and P fertilizers increased with progress of the experiment. The impact of K fertilizer showed no increase in grain yield during the initial 6 years (1982-1987), moderate increase in the next 5 years (1988-1992), and considerable increase in the last 9 years (1993-2001). The straw yield trend was similar to grain yield. Accumulation and distribution of NO3--N in soil was significantly affected by annual fertilizations. Mineral fertilizers (NP and NPK) led to NO3--N accumulation in most subsoil layers, with major impact in the 20-140 cm depth. The combination of mineral fertilizers and farmyard manure (MNP and MNPK) reduced soil NO3--N accumulation in comparison to mineral fertilizers. It can be argued that

  8. The Effects of Long Term Nitrogen Fertilization on Soil Respiration in Rocky Mountain National Park

    Science.gov (United States)

    Allen, J.; Denning, S.; Baron, J.

    2015-12-01

    Anthropogenic activities contribute to increased levels of nitrogen deposition and elevated CO2 concentrations in terrestrial ecosystems. The role that soils play in biogeochemical cycles is an important area of uncertainty in ecosystem ecology. One of the main reasons for this uncertainty is that we have limited understanding of belowground microbial activity and how this activity is linked to soil processes. In particular, elevated CO2 may influence soil nitrogen processes that regulate nitrogen availability to plants. Warming and nitrogen fertilization may both contribute to loss of stored carbon from mountain ecosystems, because they contribute to microbial decomposition of organic matter. To study the effects of long-term nitrogen fertilization on soil respiration, we analyzed results from a 25-year field experiment in Rocky Mountain National Park. Field treatments are in old growth Engelmann spruce forests. Soil respiration responses to the effects of nitrogen fertilization on soil carbon cycling, via respiration, were investigated during the 2013 growing season. Soil moisture, temperature, and respiration rates were measured in six 30 x 30 m plots, of the six plots three are fertilized with 25 kg N ha-1 yr-1 as ammonium nitrate (NH4NO3) pellets and three receives ambient atmospheric nitrogen deposition (1-6 kg N/ha/yr) in Rocky Mountain National Park. We found that respirations rates in the fertilized plots were not significantly higher than respiration rates in the unfertilized plots. We speculate that acclimation to long-term fertilization and relatively high levels of nitrogen deposition in the control plots both contribute to the insensitivity of soil respiration to fertilization at this site.

  9. [Effect of long-term fertilization on microbial community functional diversity in black soil].

    Science.gov (United States)

    Liu, Jing-xin; Chi, Feng-qin; Xu, Xiu-hong; Kuang, En-jun; Zhang, Jiu-ming; Su, Qing-rui; Zhou, Bao-ku

    2015-10-01

    In order to study the effects of long-term different fertilization on microbial community functional diversity in arable black. soil, we examined microbial metabolic activities in two soil la- yers (0-20 cm, 20-40 cm) under four treatments (CK, NPK, M, MNPK) from a 35-year continuous fertilization field at the Ministry of Agriculture Key Field Observation Station of Harbin Black Soil Ecology Environment using Biolog-ECO method. The results showed that: in the 0-20 cm soil layer, combined application of organic and inorganic fertilizer(MNPK) increased the rate of soil microbial carbon source utilization and community metabolism richness, diversity and dominance; In the 20-40 cm layer, these indices of the MNPK treatment was lower than that of the NPK treat- ment; while NPK treatment decreased soil microbial community metabolism evenness in both layers. Six groups of carbon sources used by soil microbes of all the treatments were different between the two soil layers, and the difference was significant among all treatments in each soil layer (P functional diversity in both tillage soil layer and down soil layers, and chemical fertilization alone had a larger influence on the microbial community functional diversity in the 20-40 cm layer.

  10. [Effects of long-term different fertilizations on biomass and nutrient content of maize root].

    Science.gov (United States)

    Cai, Miao; Meng, Yan; Mohammad Amin, Ahmadzai; Zhou, Jian-bin

    2015-08-01

    Taking two long-term local field trials at the south edge of the Loess Plateau, which were found in 1990 and 2003, respectively, as test subjects, the effects of different fertilization practices on the maize root biomass and nutrient content were investigated in this paper. Maize roots in the 0-20 cm top soil post-maize harvest from the different fertilization practices were collected by hand in October 2011. The results showed that compared with control without fertilization and N, NK, or PK treatments, the NP, NPK, fertilizers plus manure (M1NPK and M2NPK) or plus straw return (SNPK) treatments significantly increased the dry mass of maize root. The C, N, P and K contents in maize roots in the NP, NPK, M1 NPK, M2NPK and SNPK treatments were also significantly higher than those of control, especially in the NPK plus organic manure treatments (M1 NPK and M2NPK) in the trial. Compared with the N fertilizer free treatment (N0), root biomass in the 120 kg N · hm(-2) (N120) and 240 kg N · hm(-2) ( N240) fertilization treatments increased by 38% and 45%, respectively, but there was no significant difference between N120 and N240 treatments. Nitrogen fertilizer application (N120 and N240) also improved the C, N, P and K contents in maize root. The water soluble organic C and total soluble N contents of maize root in the NP, NPK, M1NPK, M2NPK, SNPK and the N120 and N240 treatments were greater than those of control and other treatments. Otherwise, the cellulose and lignin contents in maize roots declined in the NPK, M1NPK, M2NPK, and SNPK treatments compared with other treatments. So the root C/N and lignin/N ratios in the control, PK and N0 treatments were significantly higher than those in the NP, NPK, M1NPK, M2NPK and SNPK treatments. We concluded that the optimum fertilization (e. g., NP, NPK, MNPK and SNPK treatments) could increase maize root growth and nutrient content and improve soil fertility and carbon sequestration through root residue into soil.

  11. Long term effects of ash fertilization of reed canary grass; Laangtidseffekter av askgoedsling vid roerflensodling

    Energy Technology Data Exchange (ETDEWEB)

    Palmborg, Cecilia; Lindvall, Eva

    2011-03-15

    harvest. The main component of the ash is silica and silica concentrations are higher when reed canary grass is grown on clay soil than on peat soil. In an earlier project within the department of agricultural research for northern Sweden, SLU Umea, reed canary grass growing on peat soil was fertilized with ash from cocombustion of reed canary grass and sorted municipal waste. This ash was beneficial for the growth of the grass and did not give increased heavy metal contents. However the experiment only lasted two years so no conclusions could be drawn about long-term effects. Crop yields and elemental composition of the crop: The yields varied very much from year to year. The first two production years, 2004 and 2005 the yield was at expected levels, 6000-7000 kg dry matter per ha and year. After that, 2006-2009 the yields have been lower than expected, 1500 - 4000 kg dry matter per ha and year. The reason for this is not known, but it could be related to climate or pests. There were no significant differences in yield between the treatments. Samples from each plot from the last harvest and stored samples from 2004 were analyzed for nutrient and heavy metal content. There were only minor significant differences between the treatments: The ash and the potassium and calcium concentrations 2009 in grass from treatment A, ash from co-combustion of reed canary grass and waste, was slightly higher than in the NPK fertilized control. The magnesium concentration in 2009 was slightly higher in grass fertilized with reed canary grass ash than in the control grass. Element balances and soil concentrations of elements: Because of the low yield levels the amounts of P and K applied were much higher than the removal with harvests (Table 2). This resulted in an increase in plant available P and K in the top soil between 2003 and 2008 (Table 3). However, in the subsoil there was a decrease especially in plant available P. The only significant differences in soil nutrients between the

  12. Residual Long-Term Effects of Forest Fertilization on Tree Growth and Nitrogen Turnover in Boreal Forest

    Directory of Open Access Journals (Sweden)

    Fredrik From

    2015-04-01

    Full Text Available The growth enhancing effects of forest fertilizer is considered to level off within 10 years of the application, and be restricted to one forest stand rotation. However, fertilizer induced changes in plant community composition has been shown to occur in the following stand rotation. To clarify whether effects of forest fertilization have residual long-term effects, extending into the next rotation, we compared tree growth, needle N concentrations and the availability of mobile soil N in young (10 years Pinus sylvestris L. and Picea abies (L. H. Karst. stands. The sites were fertilized with 150 kg·N·ha−1 once or twice during the previous stand rotation, or unfertilized. Two fertilization events increased tree height by 24% compared to the controls. Needle N concentrations of the trees on previously fertilized sites were 15% higher than those of the controls. Soil N mineralization rates and the amounts of mobile soil NH4-N and NO3-N were higher on sites that were fertilized twice than on control sites. Our study demonstrates that operational forest fertilization can cause residual long-term effects on stand N dynamics, with subsequent effects on tree growth that may be more long-lasting than previously believed, i.e., extending beyond one stand rotation.

  13. Effect of Long-Term Application of Chemical Fertilizers on microbial biomass and Functional Diversity of a Black Soil

    Institute of Scientific and Technical Information of China (English)

    KONG Wei-Dong; ZHU Yong-Guan; FU Bo-Jie; HAN Xiao-Zeng; ZHANG Lei; HE Ji-Zheng

    2008-01-01

    An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.

  14. [Effects of long-term fertilization on soil organic nitrogen components in paddy soil derived from red earth].

    Science.gov (United States)

    Zong, Hai-ying; Wang, Kai-rong; Xie, Xiao-li

    2008-08-01

    A 16-year long-term fertilization experiment was conducted on paddy soil derived from red earth to investigate the effects of different fertilization patterns on the concentrations of soil organic nitrogen (N) components. When chemical fertilizers were applied only, the soil nitrogen content was slightly influenced. Organic fertilization, especially its combination with chemical fertilization, could significantly increase the contents of soil mineralizable N and organic nitrogen by 55.2% and 38.8%, respectively. In addition, organic fertilization could significantly improve the components of acid hydrolysable N, and lead to the increase of ammonium N (AN) , amino sugar N (ASN), and hydrolysable unidentified N (HUN) by 36.5%, 68.4%, and 73.9%, respectively. When the organic fertilization was combined with chemical fertilization, soil amino acid N content was increased by 71.1%, while HUN content was decreased by 34.5%. In all fertilization treatments, the cumulative amount of soil mineralized N increased with increasing incubation time. The content of soil mineralized N under organic fertilization and its combination with chemical fertilization was higher than that under chemical fertilization.

  15. Effects of Long-Term Application of Inorganic Fertilizers on Biochemical Properties of a Rice-Planting Red Soil

    Institute of Scientific and Technical Information of China (English)

    ZHONG Wen-Hui; CAI Zu-Cong; ZHANG He

    2007-01-01

    A long-term experiment was set up in Yingtan of Jiangxi Province to investigate the effects of long-term application of inorganic fertilizers on the biochemical properties of a rice-planting soil derived from Quaternary red earth. Noncultivated soils are extremely eroded and characterized by a low pH and deficiencies in available nutrients, in particular P and N. After 13 years of inorganic fertilization in cultivation for double-cropped rice, the biochemical properties of the soil were changed. The nitrification potential and urease activity were higher in the treatments with N application than those without N application. Acid phosphatase activity and dehydrogenase activity were also higher in the treatments with P application than in those without P application. The dehydrogenase activity correlated well with the concentrations of both total P and hydrolysable N and with rice crop yield, suggesting that dehydrogenase activity might be a suitable indicator for improvement in soil fertility.

  16. Long-term effects of low fertility in the region of former Yugoslavia

    Directory of Open Access Journals (Sweden)

    Nikitović Vladimir

    2016-01-01

    Full Text Available After the dissolution of the socialist Yugoslavia (SFRY in 1991, the quality and availability of demographic and migration statistics in the region as a whole, and especially in some of its parts are deteriorated. In addition, census rounds are not being held regularly throughout the region as of 1991. Thus, producing population projections has become rather challenging in comparison to the period of SFRY. This paper made an effort in order to overcome obstacles in terms of historic data and jump-off projection values for the whole region in accordance with adjusted data from national records. Until 1991, population of the region had been increasing almost linearly. Although SFRY was characterized by significant sub-regional differences in terms of the beginning and the pace of demographic transition, the current total fertility rate throughout the region is below 2.1. The aim of the paper is to consider the long-term implications of low fertility and whether in this respect there would be a demographic homogenization of the region. For that purpose, we relied on the UN WPP2015 model used by the UN Population Division for producing its 2015 World Population Prospects. It enabled several important features from the viewpoint of the main tasks of the paper: the methodologically consistent datasets on main demographic indicators, probabilistic approach for modelling and forecasting fertility and mortality, the opportunity to adjust initial datasets for known issues on data quality (Serbia, Kosovo, Bosnia & Herzeg., and ability to adjust data distribution according to the former administrative division of SFRY. The last one was of particular importance as it allowed us to take into account the well-known diversity of fertility patterns in Serbia (Vojvodina, Central Serbia and Kosovo, and to make a distinction in projection results between the sub-regions differed by the onset and tempo of fertility transition. The UN concept of post

  17. Effects of Long-Term Fertilization on Distribution of Organic Matters and Nitrogen in Cinnamon Soil Macro-Aggregates

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Soil samples collected from a 25-year long-term fertilizer experiment carried out on the Earth-cumulic-Orthic Anthrosols in semi-humid farmland ecological system, were used to study the distribution of soil organic matters, total nitrogen, nitrate nitrogen, and ammoniate nitrogen in different grades of soil macro-aggregates in order to study the effects of long-term application of organic manures in combination with chemical fertilizers. It is showed that the percentage of mass of the soil macro-aggregates with long-term application of fertilizers with sizes of 5-2 mm is increased compared with that of the samples with no fertilizer. It is easier to form lager size soil macro-aggregates by the long-term application of organic manures in combination with chemical fertilizers. The contents of organic matters, total nitrogen and nitrate nitrogen are all higher after treatments with different combinations of fertilizers, while there is a little effect on the contents of ammoniate nitrogen. The contents of organic matters, total nitrogen in the grades of soil macro-aggregates from the plough layers of the treated farmland exhibited significant difference. Moreover, the contents of organic matters and total nitrogen in the soil macro-aggregates with the size of 1-0.25 mm is the highest in all treated soil samples. The contents of nitrate nitrogen in soil macro-aggregates increased with the increasing of soil macro-aggregate size except those applied with chemical fertilizer and lower amount of corn stover. The results of correlation analysis revealed that there exists a significantly positive correlation between the percentage of mass of soil macro-aggregates with the size of 5-2 mm and the contents of organic matters, total nitrogen and nitrate nitrogen in the soil samples. However, the correlation between the percentage of mass of soil macro-aggregates with the size of 1-0.25 mm and the contents of total nitrogen and nitrate nitrogen is significantly negative. The

  18. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Science.gov (United States)

    Liu, Enke; Yan, Changrong; Mei, Xurong; Zhang, Yanqing; Fan, Tinglu

    2013-01-01

    An understanding of the dynamics of soil organic carbon (SOC) as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm) in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK), nitrogen fertilizer (N), nitrogen and phosphorus (P) fertilizers (NP), straw plus N and P fertilizers (NP+S), farmyard manure (FYM), and farmyard manure plus N and P fertilizers (NP+FYM). Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC) in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM) in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  19. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Directory of Open Access Journals (Sweden)

    Enke Liu

    Full Text Available An understanding of the dynamics of soil organic carbon (SOC as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK, nitrogen fertilizer (N, nitrogen and phosphorus (P fertilizers (NP, straw plus N and P fertilizers (NP+S, farmyard manure (FYM, and farmyard manure plus N and P fertilizers (NP+FYM. Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC, dissolved organic carbon (DOC and microbial biomass carbon (MBC in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  20. Effect of fertilization on soil phosphorus in a long-term field experiment in southern Finland

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    A. JAAKKOLA

    2008-12-01

    Full Text Available A field experiment was established in 1978 on a loam soil (pH in CaCl 2 7.1 to monitor gradual changes in the soil P status as response to different P fertilization regimes. For 18 years, cereals or grass were cultivated without P fertilization (P 0 or with annual P application of 35 kg ha -1 (P 1 or 70- 79 kg P ha -1 and 71-83 kg K ha -1 (P 2 K. The effects of the treatments on the crop yield varied yearly. The Chang and Jackson fractionation analysis revealed that fertilizer P not taken up by the plant crops was mostly in the NH 4 F extract and to a lesser extent in the NaOH extract. The NH 4 F-extractable P proved also to be the main P source for plants. However, the changes in the reserves of inorganic and organic P did not agree very well with the calculated P balance in soil (applied P minus plant P uptake. This disproportion was partly explained by the soil movement from plots to the neighbouring ones during the experiment. Phosphorus extractable in acid ammonium acetate or water decreased gradually when no P was applied and increased with increasing P accumulation. The changes in the inorganic P reserves due to different P fertilization history were reflected a little more sensitively in the water extraction test than in the acid acetate test.;

  1. Effects of soil biota influenced by long-term organic and chemical fertilizers on rice growth and resistance to insects

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    Linhui Jiang

    2016-08-01

    Full Text Available Fertilization plays an important role in soil quality, food supply and security. Although promoting soil biological development is considered as one of the most critical components that organic fertilizers exert on soil compared with chemical fertilization, less attention has been paid to the fertilization-derived influence on crop growth and insect-resistance via soil biota. Understanding the role of soil biota in crop growth and resistance to insects would not only help explain the biological mechanisms of the fertilization effects on soil functions, but also help identify integrative management techniques for soils and crops. Soil suspension was extracted from long-term organically fertilized soils and chemically fertilized soils. Then, the soil suspension was sterilized or non-sterilized to investigate the soil biota’s effects on rice growth and insect-resistance through a soil-free cultured method. Results showed that soil biota and fertilization significantly affected soil nutrient status (P < 0.01. Soil biota decreased soil ammonium content, rice biomass, shoot nitrogen content and the biomass of Nilaparvata lugens, but increased soil nitrate content, rice root-shoot ratio and the contents of root nitrogen, soluble sugar and phenolics (P < 0.05. Meanwhile, soil biota from organically fertilized soils promoted the synthesis of shoot soluble sugar and shoot phenolics. With the addition of Nilaparvata lugens, soil biota significantly reduced rice nitrogen uptake and promoted phenolic synthesis (P < 0.05. Collectively, soil biota, especially from organically fertilized soils, promoted rice resistance traits by altering the nutrient allocation of rice between aboveground and belowground, and by increasing the root-shoot ratio and the synthesis of phenols.

  2. [Effects of different long-term fertilization patterns on Fuji apple yield, quality, and soil fertility on Weibei Dryland, Shaanxi Province of Northwest China].

    Science.gov (United States)

    Zhao, Zuo-Ping; Tong, Yan-An; Liu, Fen; Wang, Xiao-Ying

    2013-11-01

    A 7-year (2003-2010) located field experiment was conducted to evaluate the effects of different long-term fertilization patterns on the Fuji apple yield, quality, and soil fertility on the Weibei Dryland, Shaanxi Province of Northwest China. Seven treatments were installed, i. e., no fertilization (CK), inorganic P and K fertilization (PK), inorganic N and K fertilization (NK), inorganic N and P fertilization (NP), inorganic N, P, and K fertilization (NPK), swine manure (M), and half inorganic N, P, and K combined with half swine manure (NPKM). Each treatment had three replications. Fertilization increased the apple yield. The average yield in the 7 years under fertilization was increased by 14.4%-63.8%, as compared to the CK. The average yield decreased in the order of NPKM > NPK > or = M > NP > or = NK > PK > CK. In treatments NPKM, M, and NPK, the fruit sugar/acid (S:A) ratio, vitamin C, soluble solid, and hardness tended to be increased with time, with a smaller yearly fluctuation in treatments NPKM and M. In treatment NPKM, the S:A ratio and vitamin C increased by 30.9% and 17.5%, respectively after five years, as compared to the CK. Long-term rational fertilization increased the soil organic matter (SOC) content in 0-20 cm layer, with the largest increment in treatments NPKM and M (28.8% and 29.3%, respectively). The soil available N, P, and K contents in all layers in treatments NPK, NPKM, and M increased significantly, and the soil available N content in 0-20, 20-40, and 40-60 cm layers in treatment NPK was increased by 22.7%, 37.3%, and 53.4%, respectively. As compared to treatment NPK, the soil available P content in treatment NPKM was increased by 18.7%. In all fertilization treatments, the soil available Pcontent was significantly higher in upper layer than in lower layer.

  3. Long-Term Effect of Fertilizer and Rice Straw on Mineral Composition and Potassium Adsorption in a Reddish Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    LIAO Yu-lin; ZHENG Sheng-xian; NIE Jun; XIE Jian; LU Yan-hong; QIN Xiao-bo

    2013-01-01

    Increasing K+adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K+ adsorption because of changes in the chemical and mineralogical properties of a rice (Oryza sativa L.). The aims of this study were (i) to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagram-decomposition method;(ii) to measure K+adsorption isotherms before and after H2O2 oxidation of organic matter, and (iii) to investigate whether K+adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr long-term fertilization treatments caused little change in soil organic C (SOC) but a large variation in soil mineral composition. The whole-clay fraction (<5μm) corresponded more to the fertilization treatment than the fine-clay fraction (<1μm) in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage of illite peak area in the<5μm soil particles (R=-0.946, P<0.0006). Different fertilization treatments gave significantly different results in K+adsorption. The SOC oxidation test showed positive effects of SOC on K+adsorption at lower K+concentration ( 120 mg L-1) and negative effects at higher K+concentration (240 mg L-1). The K+adsorption by soil clay minerals after SOC oxidization accounted for 60-158%of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K+adsorption. The K+adsorption potential was significantly correlated to the amount of poorly crystallized illite present (R=0.879, P=0.012). The availability of adsorbed K+for plant growth needs further study.

  4. The effects of long-term fertilization on the temporal stability of alpine meadow communities

    NARCIS (Netherlands)

    Yang, Z.; Ruijven, van J.; Du, G.

    2011-01-01

    The aim of the study was to investigate how plant species’ composition, soil parameters and nutrient concentrations in plant biomass differ between fertilized and control plots 62 years after the last fertilizer application on a sub-alpine grassland. A piece of land called the Grass Garden (GG), fer

  5. Effects of long-term phosphorus fertilization and straw incorporation on phosphorus fractions in subtropical paddy soil

    Institute of Scientific and Technical Information of China (English)

    LI Yu-yuan; YANG Rui; GAO Ru; WEI Hong-an; CHEN An-lei; LI Yong

    2015-01-01

    Study on soil phosphorus (P) fraction is an important aspect in probing the mechanisms of soil P accumulation in farm-land and mitigating its losing risk to the environment. We used a sequential extraction method to evaluate the impacts of long-term fertilization and straw incorporation on inorganic, organic, and residual P (Pi, Po, and Pre) fractions in the plow layer (0–20 cm) of acidic paddy soil in southern China. The experiment comprised of six treatments:(i) no fertilizer control (CK); (i ) straw incorporation and green manure (SG); (i i) nitrogen and P fertilizer (NP); (iv) NP+SG; (v) NP+K fertilizer (NPK);and (vi) NPK+SG. The results showed that, compared to the initial total soil P content (TSP, 600 mg kg–1 in 1990), long-term (20 years) combined continuous P fertilizer and SG signiifcantly increased P accumulation (by 13–20%) while single fertilization (39.3 kg P ha–1 yr–1) could maintain soil P status at the most. The average soil P fractions comprised of extractable Pi, Po, and Pre by 51.7, 33.4, and 14.9%in total soil P, respectively. With comparison of no fertilizer addition (CK), long-term single fertilization signiifcantly (P0.05), our data indicate that SG may partial y substitute for fertilizer P input and minimizing soil P accumulation and subsequent environmental risk in the subtropical paddy soil.

  6. Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to illustrate the change of nitrogen (N) supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil Soil total N (TN) and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-insoluble N, amino acid N and ammonium N in the soil increased significantly (P < 0.05) with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased (P < 0.05) hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.

  7. Long-term effects of fertilizer on soil enzymatic activity of wheat field soil in Loess Plateau, China.

    Science.gov (United States)

    Hu, Weigang; Jiao, Zhifang; Wu, Fasi; Liu, Yongjun; Dong, Maoxing; Ma, Xiaojun; Fan, Tinglu; An, Lizhe; Feng, Huyuan

    2014-12-01

    The effects of long-term (29 years) fertilization on local agro-ecosystems in the Loess Plateau of northwest China, containing a single or combinations of inorganic (Nitrogen, N; Phosphate, P) and organic (Mature, M Straw, S) fertilizer, including N, NP, SNP, M, MNP, and a control. The soil enzymes, including dehydrogenase, urease, alkaline phosphatase, invertase and glomalin, were investigated in three physiological stages (Jointing, Dough, and Maturity) of wheat growth at three depths of the soil profile (0-15, 16-30, 31-45 cm). We found that the application of farmyard manure and straw produced the highest values of soil enzymatic activity, especially a balanced applied treatment of MNP. Enzymatic activity was lowest in the control. Values were generally highest at dough, followed by the jointing and maturity stages, and declined with soil profile depth. The activities of the enzymes investigated here are significantly correlated with each other and are correlated with soil nutrients, in particular with soil organic carbon. Our results suggest that a balanced application of fertilizer nutrients and organic manure (especially those containing P) has positive effects on multiple soil chemical parameters, which in turn enhances enzyme activity. We emphasize the role of organic manure in maintaining soil organic matter and promoting biological activity, as its application can result in a substantial increase in agricultural production and can be sustainable for many years.

  8. Effects of long-term differential fertilization on eukaryotic microbial communities in an arable soil: a multiple barcoding approach.

    Science.gov (United States)

    Lentendu, Guillaume; Wubet, Tesfaye; Chatzinotas, Antonis; Wilhelm, Christian; Buscot, François; Schlegel, Martin

    2014-07-01

    To understand the fine-scale effects of changes in nutrient availability on eukaryotic soil microorganisms communities, a multiple barcoding approach was used to analyse soil samples from four different treatments in a long-term fertilization experiment. We performed PCR amplification on soil DNA with primer pairs specifically targeting the 18S rRNA genes of all eukaryotes and three protist groups (Cercozoa, Chrysophyceae-Synurophyceae and Kinetoplastida) as well as the ITS gene of fungi and the 23S plastid rRNA gene of photoautotrophic microorganisms. Amplicons were pyrosequenced, and a total of 88,706 quality filtered reads were clustered into 1232 operational taxonomic units (OTU) across the six data sets. Comparisons of the taxonomic coverage achieved based on overlapping assignment of OTUs revealed that half of the eukaryotic taxa identified were missed by the universal eukaryotic barcoding marker. There were only little differences in OTU richness observed between organic- (farmyard manure), mineral- and nonfertilized soils. However, the community compositions appeared to be strongly structured by organic fertilization in all data sets other than that generated using the universal eukaryotic 18S rRNA gene primers, whereas mineral fertilization had only a minor effect. In addition, a co-occurrence based network analysis revealed complex potential interaction patterns between OTUs from different trophic levels, for example between fungivorous flagellates and fungi. Our results demonstrate that changes in pH, moisture and organic nutrients availability caused shifts in the composition of eukaryotic microbial communities at multiple trophic levels.

  9. Long-term effect of tillage, nitrogen fertilization and cover crops on soil organic carbon and total nitrogen content

    OpenAIRE

    2011-01-01

    Metadata only record No-till practices, in conjunction with cover crops and nitrogen fertilization, have been shown to augment soil organic carbon content and total nitrogen content. However, interactions between these components in a no-till system are not well-known. This study offers a long-term (1993-2008) comparative analysis of conventional versus no-till practices as well as a some insight regarding the synergies between no-till, nitrogen fertilization, and cover crops. Maize, wheat...

  10. The long-term effects of superovulation on fertility and sexual behavior of male offspring in mice.

    Science.gov (United States)

    Wei, Zeng-Tao; Lu, Xi-Lan; Zhang, Gang; Yu, Jing; Li, Hua; Jia, Gui-Hua; Li, Jun-Tao; Zhang, Jian-Min

    2014-05-01

    To evaluate the long-term effects of superovulation on fertility and sexual behavior of male offspring in mice. The mice were superovaluted, and the fertility of male offspring (F1 generation and F2 generation) were evaluated in terms of the percentage of plugs and pregnancies, serum testosterone concentrations, and sperm motility. Furthermore, the sexual behavior of male offspring and sex ratio (F1 generation and F2 generation) were measured. There were no significant differences in the percentage of plug and pregnancies, serum testosterone concentrations, sperm motilities and sex ratio between the offspring in naturally conceived group and superovulation groups (both F1 generation and F2 generation). The sperm hyperactivity at 90 min after incubation of F1 generation in naturally conceived group were higher than that of F1 generation in superovulation group, but the differences did not reach statistical significance. The offspring produced by superovaluted oocytes (both F1 generation and F2 generation) did not exhibit significant alterations in sexual behavior. No significant alterations were found in fertility and sexual behavior of male offspring in mice produced by superovaluted oocytes compared with those of naturally conceived offspring.

  11. [Effects of long-term fertilization on soil organic carbon pool and carbon sequestration under double rice cropping].

    Science.gov (United States)

    Sun, Yu-Tao; Liao, Yu-Lin; Zheng, Sheng-Xian; Nie, Jun; Lu, Yan-Hong; Xie, Jian

    2013-03-01

    This paper studied the effects of 30 years (1981-2010) fertilization with chemical N, P, and K, pig manure (PM), and rice straw (RS) on the soil organic carbon (SOC) and its components contents under intensive double rice cropping. The experiment was established on a typic Hapli-Stagnic Anthrosols in Hunan in 1981, and the soil samples were collected in November 2010. In treatment NPK, the contents of SOC, particulate organic C (POC), and KMnO4-oxidizable C (KMnO4-C) were higher than those in treatments NP and NK. The combined application of chemical and organic fertilizers (treatments NK+PM, NP+RS, and NPK+RS) made the contents of SOC, POC, and KMnO4-C have a significant increase, as compared with chemical fertilizations. Treatment NK+PM had the highest contents of SOC (84.71 t C.hm-2), POC (8.94 t C.hm-2), and KMnO4-C (21.09 t C.hm-2) in top soil (0-45 cm), followed by treatment NPK+RS. Treatment NK+PM had the highest C sequestration (485 kg C.hm-2.a-1) , followed by treatment NPK+RS (375 kg C.hm-2.a-1). The C sequestration efficiency (CSE) of SOC in the treatments of chemical fertilizers plus pig manure or rice straw was obviously higher than that in the treatments of chemical fertilizations, and the CSE of the POC in fertilization treatments (ranging from 0.4% and 1.2%) was lower than that of the KMnO4-C (ranging from 3.0% to 8.3%). By using the values of humification constant (h) and the decay constant (k) in Jenkinson' s equation, it was possible to predict the SOC storages in different treatments in the year 2010; and by using Jenkinson' s equation, it was possible to calculate the C input required to maintain the SOC storages in the year 1981 (AE). The increase of the SOC in treatments NK+PM, NP+RS, and NPK+RS was due to the annual C input being higher than the AE. It was considered that in the double rice cropping areas in subtropical region of China, long-term application of chemical fertilizers combined with pig manure or rice straw could promote the

  12. [Effects of long-term fertilization on microbial biomass carbon and nitrogen and on carbon source utilization of microbes in a red soil].

    Science.gov (United States)

    Sun, Feng-xia; Zhang, Wei-hua; Xu, Ming-gang; Zhang, Wen-ju; Li, Zhao-qiang; Zhang, Jing-ye

    2010-11-01

    In order to explore the effects of long-term fertilization on the microbiological characters of red soil, soil samples were collected from a 19-year long-term experimental field in Qiyang of Hunan, with their microbial biomass carbon (MBC) and nitrogen (MBN) and microbial utilization ratio of carbon sources analyzed. The results showed that after 19-year fertilization, the soil MBC and MBN under the application of organic manure and of organic manure plus inorganic fertilizers were 231 and 81 mg x kg(-1) soil, and 148 and 73 mg x kg(-1) soil, respectively, being significantly higher than those under non-fertilization, inorganic fertilization, and inorganic fertilization plus straw incorporation. The ratio of soil MBN to total N under the application of organic manure and of organic manure plus inorganic fertilizers was averagely 6.0%, significantly higher than that under non-fertilization and inorganic fertilization. Biolog-ECO analysis showed that the average well color development (AWCD) value was in the order of applying organic manure plus inorganic fertilizers = applying organic manure > non-fertilization > inorganic fertilization = inorganic fertilization plus straw incorporation. Under the application of organic manure or of organic manure plus inorganic fertilizers, the microbial utilization rate of carbon sources, including carbohydrates, carboxylic acids, amino acids, polymers, phenols, and amines increased; while under inorganic fertilization plus straw incorporation, the utilization rate of polymers was the highest, and that of carbohydrates was the lowest. Our results suggested that long-term application of organic manure could increase the red soil MBC, MBN, and microbial utilization rate of carbon sources, improve soil fertility, and maintain a better crop productivity.

  13. Drainage, liming and fertilization of organic soils. 1. Long-term effects on acid/base relations

    Energy Technology Data Exchange (ETDEWEB)

    Braekke, F.H. [Norges Landbrukshoegskole, Aas (Norway). Dept. of Forest Sciences

    1999-06-01

    Long-term changes of the acid/base relations of organic soils after drainage, fertilization and/or liming at three experimental sites - two ombrogenous and one soligenous - in south-central Norway are discussed. These sites were drained, fertilized and/or limed in 1953-1956 and sampled in 1991-1992. Drainage at the ombrogenous sites caused: insignificant shifts of pH, higher bulk densities to 40 cm depth, higher ash percentage, higher contents of N and P to 20 cm depth and reduced concentrations of total Ca, K, Mg, Na, Al and Fe in soil layers deeper than 20 cm. The soligenous site was not effectively drained; despite this, pH dropped about 0.5 unit in the surface and subsurface soil layers of the control plots, while small changes were measured for most other soil variables. The suggested reason for the pH drop is limited sulphide oxidation in the upper 20 cm drained layer. Base saturation at actual soil pH, when all treatments were included, was estimated with good precision by four regressors: pH, extractable Al, extractable Fe and extractable Ca (R{sup 2} = 0.90-0.95). Similar models explained 97-99% of the variation in base saturation at soil pH = 7.0. The lime effects at the properly drained oligotrophic sites were proportional to applied doses; for pH to 40 cm, base saturation to 60 cm, and Ca concentration to 60 cm depth. At the less well-drained soligenous site, effects were limited to the upper 30 cm layer. Both drainage and liming caused higher cation exchange capacities and proper drainage seems to be a prerequisite for the liming effect. Estimated recovery of calcium to 60 cm depth was 64-79% at the ombrogenous sites and 42-46% at the soligenous site 28 refs, 3 figs, 8 tabs

  14. Effects of long-term nitrogen fertilization on the uptake kinetics of atmospheric methane in temperate forest soils.

    Science.gov (United States)

    Gulledge, Jay; Hrywna, Yarek; Cavanaugh, Colleen; Steudler, Paul A

    2004-09-01

    To determine whether repeated, long-term NH(4) (+) fertilization alters the enzymatic function of the atmospheric CH(4) oxidizer community in soil, we examined CH(4) uptake kinetics in temperate pine and hardwood forest soils amended with 150 kg N ha(-1) y(-1) as NH(4)NO(3) for more than a decade. The highest rates of atmospheric CH(4) consumption occurred in the upper 5 cm mineral soil of the control plots. In contrast to the results of several previous studies, surface organic soils in the control plots also exhibited high consumption rates. Fertilization decreased in situ CH(4) consumption in the pine and hardwood sites relative to the control plots by 86% and 49%, respectively. Fertilization increased net N mineralization and relative nitrification rates and decreased CH(4) uptake most dramatically in the organic horizon, which contributed substantially to the overall decrease in field flux rates. In all cases, CH(4) oxidation followed Michaelis-Menten kinetics, with apparent K(m) (K(m(app))) values typical of high-affinity soil CH(4) oxidizers. Both K(m(app)) and V(max(app)) were significantly lower in fertilized soils than in unfertilized soils. The physiology of the methane consumer community in the fertilized soils was distinct from short-term responses to NH(4) (+) addition. Whereas the immediate response to NH(4) (+) was an increase in K(m(app)), resulting from apparent enzymatic substrate competition, the long-term response to fertilization was a community-level shift to a lower K(m(app)), a possible adaptation to diminish the competitiveness of NH(4) (+) for enzyme active sites.

  15. [Effect of long-term application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil].

    Science.gov (United States)

    Chen, Chun-lan; Wu, Min-na; Wei, Wen-xue

    2011-05-01

    The aim of this study was to determine the effect of long-term (16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and the phylogenetic tree showed that the amoA genes detected in our study had a similarity with the uncultured gene of amoA, which showed some similar to Nitrosospira. Otherwise, the hao genes cloned showed a relationship to the genes of cultured bacteria such as Silicibacteria, Nitrosospira and Methylococcus, and the hao genes found in the N treatment dominated in alpha-Proteobacteria. These results suggest that long-term fertilization of nitrogen had significant impacts on the diversity or community of amoA and hao genes.

  16. [Effects of long-term fertilization on pH buffer system of sandy loam calcareous fluvor-aquic soil].

    Science.gov (United States)

    Wang, Ji-Dong; Qi, Bing-Jie; Zhang, Yong-Chun; Zhang, Ai-Jun; Ning, Yun-Wang; Xu, Xian-Ju; Zhang, Hui; Ma, Hong-Bo

    2012-04-01

    Soil samples (0-80 cm) were collected from a 30-year fertilization experimental site in Xuzhou, Jiangsu Province of East China to study the variations of the pH, calcium carbonate and active calcium carbonate contents, and pH buffer capacity of sandy loam calcareous fluvor-aquic soil under different fertilization treatments. Thirty-year continuous application of different fertilizers accelerated the acidification of topsoil (0-20 cm), with the soil pH decreased by 0.41-0.70. Under different fertilization, the soil pH buffer capacity (pHBC) varied from 15.82 to 21.96 cmol x kg(-1). As compared with no fertilization, single N fertilization decreased the pHBC significantly, but N fertilization combined with organic fertilization could significantly increase the pHBC. The soil pHBC had significant positive correlations with soil calcium carbonate and active calcium carbonate contents, but less correlation with soil organic matter content and soil cation exchange capacity, suggesting that after a long-term fertilization, the sandy loam calcareous fluvor-aquic soil was still of an elementary calcium carbonate buffer system, and soil organic matter and cation exchange capacity contributed little to the buffer system. The soil calcium carbonate and active calcium carbonate contents were greater in 0-40 cm than in 40-80 cm soil layer. Comparing with soil calcium carbonate, soil active calcium carbonate was more sensitive to reflect the changes of soil physical and chemical properties, suggesting that the calcium carbonate buffer system could be further classified as soil active calcium carbonate buffer system.

  17. Effect of long-term compost and inorganic fertilizer application on background N2O and fertilizer-induced N2O emissions from an intensively cultivated soil.

    Science.gov (United States)

    Ding, Weixin; Luo, Jiafa; Li, Jie; Yu, Hongyan; Fan, Jianling; Liu, Deyan

    2013-11-01

    The influence of inorganic fertilizer and compost on background nitrous oxide (N2O) and fertilizer-induced N2O emissions were examined over a maize-wheat rotation year from June 2008 to May 2009 in a fluvo-aquic soil in Henan Province of China where a field experiment had been established in 1989 to evaluate the long-term effects of manure and fertilizer on soil organic status. The study involved five treatments: compost (OM), fertilizer NPK (nitrogen-phosphorus-potassium, NPK), half compost N plus half fertilizer N (HOM), fertilizer NK (NK), and control without any fertilizer (CK). The natural logarithms of the background N2O fluxes were significantly (P<0.05) correlated with soil temperature, but not with soil moisture, during the maize or wheat growing season. The 18-year application of compost alone and inorganic fertilizer not only significantly (P<0.05) increased soil organic carbon (SOC) by 152% and 10-43% (respectively), but also increased background N2O emissions by 106% and 48-76% (respectively) compared with the control. Total N in soils was a better indicator for predicting annual background N2O emission than SOC. The estimated emission factor (EF) of mineralized N, calculated by dividing annual N2O emission by mineralized N was 0.13-0.19%, significantly (P<0.05) lower than the EF of added N (0.30-0.39%). The annual N2O emission in the NPK, HOM and OM soils amended with 300 kg ha(-1) organic or inorganic N was 1427, 1325 and 1178 g N ha(-1), respectively. There was a significant (P<0.05) difference between the NPK and OM. The results of this study indicate that soil indigenous N was less efficiently converted into N2O compared with exogenous N. Increasing SOC by compost application, then partially increasing N supply to crops instead of adding inorganic N fertilizer, may be an effective measure to mitigate N2O emissions from arable soils in the North China plain. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Long-term effect of mineral fertilizers and amendments on microbial dynamics in an alfisol of Western Himalayas.

    Science.gov (United States)

    Mahajan, S; Kanwar, S S; Sharma, S P

    2007-03-01

    The microbial dynamics expressed in terms of culturable microbial populations i.e. bacteria, fungi, actinomycetes and Azotobacter were measured after 33 years of continuous application of mineral fertilizers and amendments to an acid alfisol. The bacterial, fungal and Azotobacter populations were maximum in plots treated with mineral fertilizers and FYM (100%NPK+FYM) while actinomycetes population was maximum in mineral fertilizes and lime treated plots (100%NPK+Lime). The bacterial population decreased and fungal population increased with increasing levels of NPK i.e. from 50% to 150%NPK. Bacillus species of bacteria and Gliocladium, Aspergillus and Rhizopus species of fungi were the main dominating culturable microorganisms in all the treatments. The FYM and lime amended plots sustained crop productivity and microbial populations at higher levels than rest of the mineral fertilizer treatments. The nitrogenous fertilizers alone had the most deleterious effect on crop productivity and the biological soil environment.

  19. [Effects of long-term fertilization on organic carbon functional groups in black soil as revealed by synchrotron radiation soft X-ray near-edge absorption spectroscopy].

    Science.gov (United States)

    Wang, Nan; Wang, Shuai; Wang, Qing-He; Dong, Pei-Bo; Li, Cui-Lan; Zhang, Jin-Jing; Gao, Qiang; Zhao, Yi-Dong

    2012-10-01

    A 20 years (1984-2004) stationary field experiment was conducted to evaluate the effects of long-term application of chemical fertilizers (N or NPK) alone or in combination with low (0.125 kg x hm(-2)) or high dose of corn stalk (0.25 kg x hm(-2)) on organic carbon functional groups in black soil using synchrotron radiation soft X-ray near-edge absorption spectroscopy (C-1s NEXAFS). Compared with the control (CK) treatment, the aromatic C and the carboxyl C of soil increased, whereas the aliphatic C, the carbonyl C and the aliphatic C/aromatic C ratio decreased after the application of chemical fertilizer alone. After the application of chemical fertilizations in combined with corn stalk, the aromatic C decreased while the aliphatic C and the aliphatic C/aromatic C ratio increased as compared to N or NPK fertilizer treatment. And the change tendency was more obvious with the increase in the dose of corn stalk applied. Regardless of corn stalk application, the aromatic C, the aliphatic C, and the aliphatic C/aromatic C ratio were all higher for NPK than for N fertilizer treatment. The above results indicated that, compared with the no-fertilizer control treatment, the application of chemical fertilizers alone resulted in the relative proportion of aromatic compounds increased whereas that of aliphatic hydrocarbon compounds decreased. On the other hand, the relative proportion of the aliphatic hydrocarbon compounds was higher after the application of chemical fertilizers with than without corn stalk, with high than with low dose of corn stalk, and with NPK than with N fertilization. C-1s NEXAFS spectroscopy could characterize in situ the changes of organic carbon functional groups in soil under long-term stationary fertilization.

  20. Effects of Long-Term Combined Application of Organic and Mineral Fertilizers on Microbial Biomass, Soil Enzyme Activities and Soil Fertility

    Institute of Scientific and Technical Information of China (English)

    LI Juan; ZHAO Bing-qiang; LI Xiu-ying; JIANG Rui-bo; So Hwat Bing

    2008-01-01

    Soil health is important for the sustainable development of terrestrial ecosystem.In this paper,we studied the relationship between soil quality and soil microbial properties such as soil microbial biomass and soil enzyme activities in order to illustrate the function of soil microbial properties as bio-indicators of soil health.In this study,microbial biomass C and N contents(Cmic&Nmic),soil enzyme activities,and soil fertility with different fertilizer regimes were carried out based on a 15-year long-term fertilizer experiment in Drab Fluvo-aquic soil in Changping County,Beijing,China.At this site,7 different treatments were established in 1991.They were in a wheat-maize rotation receiving either no fertilizer(CK),mineral fertilizers(NPK),mineral fertilizers with wheat straw incorporated(NPKW),mineral fertilizers with incremental wheat straw incorporated(NPKW+),mineral fertilizers plus swine manure(NPKM),mineral fertilizers plus incremental swine manure(NPKM+)or mineral fertilizers with maize straw incorporated(NPKS).In different fertilization treatments Cmic changed from 96.49 to 500.12 mg kg-1,and Nmic changed from 35.89 to 101.82 mg kg-1.Compared with CK,the other treatments increased Cmic&Nmic,Cmic/Corg(organic C)ratios,Cmic/Nmic,urease activity,soil organic matter(SOM),soil total nitrogen(STN),and soil total phosphorus(STP).All these properties in treatment with fertilizers input NPKM+ were the highest.Meantime,long-term combined application of mineral fertilizers with organic manure or crop straw could significantly decrease the soil pH in Fluvo-aquic soil(the pH around 8.00 in this experimental soil).Some of soil microbial properties(Cmic/Nmic,urease activity)were positively correlated with soil nutrients.Cmic/Nmic was significantly correlated with SOM and STN contents.The correlation between catalase activity and soil nutrients was not significant.In addition,except of catalase activity,the soil pH in this experiment was negatively correlated with soil

  1. Long-Term Effect of Organic and Mineral Fertilization on Soil Physical Properties Under Greenhouse and Outdoor Management Practices

    Institute of Scientific and Technical Information of China (English)

    J. F. HERENCIA; P. A. GARC(I)A-GALAV(I)S; C. MAQUEDA

    2011-01-01

    To evaluate the use of organic amendments as an alternative to conventional fertilization,a 10-year experiment on a loam soil was conducted under a crop rotation system in both greenhouse and outdoor plots applied with chemical fertilizers (NPK) and vegetal compost (organic fertilizer) in the Guadalquivir River Valley,Spain.The effect of these two different fertilization regimes on the soil physical properties was evaluated.Soil organic carbon (OC),soil bulk density (BD),soil water retention (WR),available water content (AWC),aggregate stability (AS),and soil physical quality (Dexter's index,S) were determined.The use of organic fertilizer increased OC and resulted in a significant increase in AS and a decrease in BD compared to the mineral fertilizer application in both greenhouse and outdoor plots.The outdoor plots showed the lowest BD values whereas the greenhouse plots showed the highest AS values.In the last years of the 10-year experiment the S parameter was significantly higher in organic fertilizer plots,especially for greenhouse plots.At the end of the study period,there were no significant differences in WR at field capacity (FC) between treatments in both systems; the AWC was also similar in the greenhouse plots but higher in the mineral outdoor plots.In mineral fertilizer treatments,a small improvement in the physical properties was also observed due to the utilization of less aggressive tillage compared with the previous intensive cropping system.Physical soil properties were correlated with soil OC.The sustainable management techniques such as the use of organic amendments and low or no tillage improved soil physical properties,despite the differences in management that logically significantly affected the results.

  2. Effect of Long-Term Potassium Fertilization on Crop Yield and Potassium Efficiency and Balance Under Wheat-Maize Rotation in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui-Min; YANG Xue-Yun; HE Xin-Hua; XU Ming-Gang; HUANG Shao-Min; LIU Hua; WANG Bo-Ren

    2011-01-01

    Sustainable potassium (K) management at different soil sites requires understanding the relationships between crop productivity and long-term K fertilizations on a regional or national scale. We analyzed responses of grain yield of wheat (Triticum aestivum L.) and maize (Zea mays L.), K efficiency, and partial balance (difference between K input through fertilizer and K output in the aboveground biomass) during 15- (1990-2005) or 18-year (1990-2008) K fertilizations at five distinctive agroecological zones across China. Compared to the inorganic nitrogen (N) and phosphorus (P) fertilization, the inorganic NPK fertilization significantly increased grain yields of wheat (21%) and maize (16%-72%) at Qiyang and Changping, where soils have low exchangeable and non-exchangeable K contents, but not at (U)rǔmqi, Yangling and Zhengzhou, where soils have a high exchangeable and non-exchangeable K and/or low N/K ratio in crop plants. Compared to the inorganic NPK fertilization, the inorganic NPK (30% N) and organic manure (70% N) fertilization (NPKM) increased grain yields of wheat (14%-40%) and maize (9%-61%) at four sites, but not at Zhengzhou. For a productivity of wheat at 2-5 t ha-1 or maize at 3-6 t ha-1, 13-26 or 9-17 kg K ha-1 were required to produce 1.0 t wheat or maize. The NP fertilization resulted in the lowest negative partial K balance and accumulated 52 kg K ha-1 year-1 less than the NPK fertilization, which accumulated 28 kg ha-1 year-1 less K than the NPKM fertilization. A re-evaluation of the site-specific fertilization effects on N/K rat io in crop plants and soil K accumulation under current NPK and NPKM fertilization is urgently needed to increase both crop yield and K use efficiency at different agroecological zones across China.

  3. Short-term and long-term effects of weed control and fertilization on growth and wood anatomy of a Populus deltoides clone

    Directory of Open Access Journals (Sweden)

    Silvia Estela Monteoliva

    2015-04-01

    Full Text Available Aims of study: The short- and long-term effects of weed control and fertilization on growth and wood anatomy of 10-y-old Populus deltoides were investigated. Weed control and fertilization usually leads to an increase the growth rate of trees, and consequently, a possible modification in the quality of produced wood. Area of study: We analyzed trees from an experimental plantation in Buenos Aires, Argentina (34° 50’ S Lat; 60° 30’ W Long. Methods: 32 trees from three treatments: mechanical weed control (M, chemical and mechanical weed control (CHM and fertilized plus chemical and mechanical weed control (CHM-F were analyzed. Basal area, fibre morphology, cell wall area and vessel size were measured in the growth ring 1, 3 and 10. Results: differences on wood anatomy among treatments were mainly observed at the third year (short-term effect. Long-term negative effects were not observed. Fertilized trees had greater proportion and quality of wood closer to pith. Research highlights: fibre and vessel differences seen in CHM and CHM-F compared to controls in year 3 could be interpreted as evidence of maturation in cambial development (thicker, longer and wider fibres and greater vessels. The CHM-F treatment had a greater proportion of wood that showed characteristics of more mature wood.

  4. [Effect of Long-term Fertilizer Application on the Stability of Organic Carbon in Particle Size Fractions of a Paddy Soil in Zhejiang Province, China].

    Science.gov (United States)

    Mao, Xia-li; Lu, Kou-ping; Sun, Tao; Zhang, Xiao-kai; He, Li-zhi; Wang, Hai-long

    2015-05-01

    Effects of chemical fertilizers and organic manure on the soil organic carbon (SOC) content in particle size fractions of paddy soil were investigated in a 17-year long-term fertilization field experiment in Zhejiang Province, China. The inherent chemical composition of silt- and clay-associated SOC was evaluated with solid-state 13C-NMR spectroscopy. Compared to CK (no fertilizer treatment), NPKRS (NPK fertilizers plus rice straw) , NPKOM (NPK fertilizers plus organic manure) , NPK (NPK fertilizers) and OM (organic manure alone) treatments significantly (P fertilizers alone, combined application of organic amendments and NPK fertilizers facilitated the storage of newly sequestered SOC in silt- and clay-sized fractions, which could be more conducive to the stability of SOC. Based on 13C-NMR spectra, both silt and clay fractions were composed of Alkyl-C, O-alkyl-C, Aromatic-C and carbonyl-C. Changes in the relative proportion of different C species were observed between silt and clay fractions: the clay fraction had relatively more Alkyl-C, carbonyl-C and less O-alkyl-C, Aromatic-C than those in the silt fraction. This might be ascribed to the fact that the organic matter complexed with clay was dominated by microbial products, whereas the silt appeared to be rich in aromatic residues derived from plants. The spectra also showed that the relative proportion of different C species was modified by fertilization practices. In comparison with organic amendments alone, the relative proportion of Alkyl-C was decreased by 9.1%-11.9% and 13.7%-19.9% under combined application of organic amendments and chemical fertilizers, for silt and clay, respectively, and that of O-alkyl-C was increased by 2.9%-6.3% and 13.4%-22.1%, respectively. These results indicated that NPKOM and NPKRS treatments reduced the decomposition rate of SOC. The aromaticity, hydrophobicity and, hence, chemical recalcitrance of silt- and clay-associated SOC in the NPK fertilizer treatments were lower than

  5. Long-term CO2 fertilization increases vegetation productivity and has little effect on hydrological partitioning in tropical rainforests

    Science.gov (United States)

    Yang, Yuting; Donohue, Randall J.; McVicar, Tim R.; Roderick, Michael L.; Beck, Hylke E.

    2016-08-01

    Understanding how tropical rainforests respond to elevated atmospheric CO2 concentration (eCO2) is essential for predicting Earth's carbon, water, and energy budgets under future climate change. Here we use long-term (1982-2010) precipitation (P) and runoff (Q) measurements to infer runoff coefficient (Q/P) and evapotranspiration (E) trends across 18 unimpaired tropical rainforest catchments. We complement that analysis by using satellite observations coupled with ecosystem process modeling (using both "top-down" and "bottom-up" perspectives) to examine trends in carbon uptake and relate that to the observed changes in Q/P and E. Our results show there have been only minor changes in the satellite-observed canopy leaf area over 1982-2010, suggesting that eCO2 has not increased vegetation leaf area in tropical rainforests and therefore any plant response to eCO2 occurs at the leaf level. Meanwhile, observed Q/P and E also remained relatively constant in the 18 catchments, implying an unchanged hydrological partitioning and thus approximately conserved transpiration under eCO2. For the same period, using a top-down model based on gas exchange theory, we predict increases in plant assimilation (A) and light use efficiency (ɛ) at the leaf level under eCO2, the magnitude of which is essentially that of eCO2 (i.e., 12% over 1982-2010). Simulations from 10 state-of-the-art bottom-up ecosystem models over the same catchments also show that the direct effect of eCO2 is to mostly increase A and ɛ with little impact on E. Our findings add to the current limited pool of knowledge regarding the long-term eCO2 impacts in tropical rainforests.

  6. Effects of long-term amendment of organic manure and nitrogen fertilizer on nitrous oxide emission in a sandy loam soil

    Institute of Scientific and Technical Information of China (English)

    DING Wei-xin; MENG Lei; CAI Zu-cong; HAN Feng-xiang

    2007-01-01

    To understand the effects of long-term amendment of organic manure and N fertilizer on N2O emission in the North China Plain,a laboratory incubation at different temperatures and soil moistures were carried out using soils treated with organic manure (OM),half organic manure plus half fertilizer N (HOM), fertilizer NPK (NPK), fertilizer NP (NP), fertilizer NK (NK), fertilizer PK (NK) and control (CK) since 1989. Cumulative N2O emission in OM soil during the 17 d incubation period was slightly higher than in NPK soil under optimum nitrification conditions (25C and 60% water-filled pore space, WFPS), but more than twice under the optimum denitrification conditions (35C and 90% WFPS). N2O produced by denitrification was 2.1-2.3 times greater than that by nitrification in OM and HOM soils, but only 1.5 times greater in NPK and NP soils. These results implied that the long-term amendment of organic manure could significantly increase the N2O emission via denitrification in OM soil as compared to NPK soil. This is quite different from field measurement between OM soil and NPK soil. Substantial inhibition of the formation of anaerobic environment for denitrification in field might result in no marked difference in N2O emission between OM and NPK soils. This is due in part to more rapid oxygen diffusion in coarse textured soils than consumption by aerobic microbes until WFPS was 75% and to low easily decomposed organic C of organic manure. This finding suggested that addition of organic manure in the tested sandy loam might be a good management option since it seldom caused a burst of N2O emission but sequestered atmospheric C and maintained efficiently applied N in soil.

  7. Effect of long-term fertilizer application in maize crop growing on chemical element leaching in Fluvisol

    Science.gov (United States)

    Simeonova, Tsetska; Stoicheva, Dimitranka; Koleva, Venelina; Sokołowska, Zofia; Hajnos, Mieczysław

    2017-04-01

    The study characterized the regime of nutrient leaching under different nitrogen and phosphorus supply of irrigated maize grown as monoculture on Fluvisol for the period 1999-2008 and additionally studied in the years 2009, 2010, and 2011. The aim of the study was to estimate the effect of longterm fertilizer application on the leaching of nutrients from the soil under maize grown as monoculture. The experiment design included four nitrogen fertilizer rates (B1-control, B5, B4, B3, B2) calculated to compensate 50, 75, 100, and 125% from the plant N uptake, respectively. The field plots were equipped with lysimeters (at 50 and 100 cm depth) for studying the relationship between the applied fertilizer rates and the nutrient concentrations in the lysimetric water. The greatest nitrogen concentration in lysimetric water was observed under variant (B3-N200 P150) throughout the study period and the highest N losses were registered (36 kg ha-1) in 2010 under the same treatment (B3). A very good correlation was found between the N rates, calcium, and magnesium losses. Lysimetric water component compensation shows that agricultural activities have only influenced the speed of weathering and had no significant effect on the rates.

  8. A long-term nitrogen fertilizer gradient has little effect on soil organic matter in a high-intensity maize production system.

    Science.gov (United States)

    Brown, Kimberly H; Bach, Elizabeth M; Drijber, Rhae A; Hofmockel, Kirsten S; Jeske, Elizabeth S; Sawyer, John E; Castellano, Michael J

    2014-04-01

    Global maize production alters an enormous soil organic C (SOC) stock, ultimately affecting greenhouse gas concentrations and the capacity of agroecosystems to buffer climate variability. Inorganic N fertilizer is perhaps the most important factor affecting SOC within maize-based systems due to its effects on crop residue production and SOC mineralization. Using a continuous maize cropping system with a 13 year N fertilizer gradient (0-269 kg N ha(-1) yr(-1)) that created a large range in crop residue inputs (3.60-9.94 Mg dry matter ha(-1) yr(-1)), we provide the first agronomic assessment of long-term N fertilizer effects on SOC with direct reference to N rates that are empirically determined to be insufficient, optimum, and excessive. Across the N fertilizer gradient, SOC in physico-chemically protected pools was not affected by N fertilizer rate or residue inputs. However, unprotected particulate organic matter (POM) fractions increased with residue inputs. Although N fertilizer was negatively linearly correlated with POM C/N ratios, the slope of this relationship decreased from the least decomposed POM pools (coarse POM) to the most decomposed POM pools (fine intra-aggregate POM). Moreover, C/N ratios of protected pools did not vary across N rates, suggesting little effect of N fertilizer on soil organic matter (SOM) after decomposition of POM. Comparing a N rate within 4% of agronomic optimum (208 kg N ha(-1) yr(-1)) and an excessive N rate (269 kg N ha(-1) yr(-1)), there were no differences between SOC amount, SOM C/N ratios, or microbial biomass and composition. These data suggest that excessive N fertilizer had little effect on SOM and they complement agronomic assessments of environmental N losses, that demonstrate N2 O and NO3 emissions exponentially increase when agronomic optimum N is surpassed.

  9. Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Crop Yield and Soil K Under Different Planting Systems

    Institute of Scientific and Technical Information of China (English)

    TAN De-shui; JIN Ji-yun; HUANG Shao-wen; LI Shu-tian; HE Ping

    2007-01-01

    Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK + St > NPK > NP + St > NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK + St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K.

  10. [Effects of different long-term fertilization on the activities of enzymes related to carbon, nitrogen, and phosphorus cycles in a red soil].

    Science.gov (United States)

    Fan, Miao-zhen; Yin, Chang; Fan, Fen-liang; Song, A-lin; Wang, Bo-ren; Li, Dong-chu; Liang, Yong-chao

    2015-03-01

    Using a microplate fluorimetric assay method, five fertilization treatments, i.e. no-fertilizer control (CK) , sole application of nitrogen (N), balanced application of nitrogen, phosphorus, and potassium fertilizer (NPK), application of pig manure (M), and combination of pig manure with balanced chemical fertilizer (MNPK) were selected to investigate the effects of different long-term fertilization regimes on the activity of five enzymes (β-1, 4-glucosidase, βG; cellobiohydrolase, CBH; β-1, 4-xylosidase, βX; β-1, 4-N-acetylglucosaminidase, NAG; acid phosphatase, AP) in a red soil sampled from Qiyang, Hunnan Province. The results showed that compared with CK treatment, N treatment had no impact on βG, βX, CBH, and NAG activities but reduced AP activity, while NPK, M and MNPK treatments increased the activities of all the five enzymes. Correlation analysis indicated that all the five enzyme activities were positively correlated with the content of nitrate (r=0.465-0.733) , the content of available phosphorus (r=0.612-0.947) , soil respiration (r=0.781-0.949) and crop yield (r=0.735-0.960), while βG, CBH and AP were positively correlated with pH (r= 0.707-0.809), only AP was significantly correlated with dissolvable organic carbon (r = -0.480). These results suggested that the activities of the measured enzymes could be used as indicators of red soil fertility under different fertilization regimes, but the five enzymes tested provided limited information on the degree of acidification induced by application of mineral nitrogen.

  11. Microcalorimetric study of the effects of long-term fertilization on soil microbial activity in a wheat field on the Loess Plateau.

    Science.gov (United States)

    Zhang, Qi; Liu, Xiaomei; Ma, Xiaojun; Fang, Jian; Fan, Tinglu; Wu, Fasi; An, Lizhe; Feng, Huyuan

    2014-12-01

    The effects of the long-term inorganic (nitrogen, N; phosphate, P) and organic (manure, M; straw, S) fertilizers/managemenet individually and in combinations (N, NP, SNP, M, and MNP) on soil microbial activity were investigated in a wheat field on the Loess Plateau, China. Microcalorimetry was used to determine microbial activity under different treatments. Nearly 30 years of consecutive fertilization has altered the culturable population of soil bacteria and fungi, the highest ones were detected in the treatments of manure and MNP, followed by the NP and SNP treatments. The microbial growth rate constant (μ/h(-1)) was significantly greater in the MNP treatment than all the other treatments. The total heat exchange values (Q/J) were the highest in the MNP and NP treatments, which were significantly different from the N and M treatments. The peak height (P(t)/μW) were significantly higher in MNP and NP treatments than in the remaining treatments. The peak time values (t(p)/h) among the MNP, NP, SNP and M, N and CK treatments were significantly different. In general, comparing with control, soil microbial activity was much higher in MNP, NP and SNP treatments, all including the phosphate fertilizer. Our results showed that the application of inorganic fertilizer and organic manure have positive effects on multiple soil chemical parameters, soil microorganism abundance and activity, and hence crop yield.

  12. [Variation characteristics of maize yield and fertilizer utilization rate on an upland yellow soil under long term fertilization].

    Science.gov (United States)

    Luo, Long-Zao; Li, Yu; Zhang, Wen-An; Xiao, Hou-Jun; Jiang, Tai-Ming

    2013-10-01

    An analysis was made on the 16-year experimental data from the long term fertilization, experiment of maize on a yellow soil in Guizhou of Southwest China. Four treatments, i. e. , no fertilization (CK), chemical fertilization (165 kg N x hm(-2), 82.5 kg P2O5 x hm(-2), and 82.5 kg K2O x hm(-2), NPK), organic manure (30555 kg x hm(-2), M), and combined applicatioin of chemical fertilizers and organic manure (NPKM), were selected to analyze the variation trends of maize yield and fertilizer use efficiency on yellow soil under effects of different long term fertilization modes, aimed to provide references for evaluating and establishing long term fertilization mode and promote the sustainable development of crop production. Overall, the maize yield under long term fertilization had an increasing trend, with a large annual variation. Treatment NPKM had the best yield-increasing effect, with the maize yield increased by 4075.71 kg x hm(-2) and the increment being up to 139.2%. Long term fertilization increased the fertilizer utilization efficiency of maize. In treatment M, the nitrogen and phosphorus utilization rates were increased significantly by 35.4% and 18.8%, respectively. Treatment NPK had obvious effect in improving potassium utilization rate, with an increment of 20% and being far higher than that in treatments M (8.7%) and NPKM (9.2%). The results showed that long term fertilization, especially the combined application of chemical fertilizers and organic manure, was of great importance in increasing crop yield and fertilizer use efficiency.

  13. Long-term fate of nitrate fertilizer in agricultural soils.

    Science.gov (United States)

    Sebilo, Mathieu; Mayer, Bernhard; Nicolardot, Bernard; Pinay, Gilles; Mariotti, André

    2013-11-05

    Increasing diffuse nitrate loading of surface waters and groundwater has emerged as a major problem in many agricultural areas of the world, resulting in contamination of drinking water resources in aquifers as well as eutrophication of freshwaters and coastal marine ecosystems. Although empirical correlations between application rates of N fertilizers to agricultural soils and nitrate contamination of adjacent hydrological systems have been demonstrated, the transit times of fertilizer N in the pedosphere-hydrosphere system are poorly understood. We investigated the fate of isotopically labeled nitrogen fertilizers in a three-decade-long in situ tracer experiment that quantified not only fertilizer N uptake by plants and retention in soils, but also determined to which extent and over which time periods fertilizer N stored in soil organic matter is rereleased for either uptake in crops or export into the hydrosphere. We found that 61-65% of the applied fertilizers N were taken up by plants, whereas 12-15% of the labeled fertilizer N were still residing in the soil organic matter more than a quarter century after tracer application. Between 8-12% of the applied fertilizer had leaked toward the hydrosphere during the 30-y observation period. We predict that additional exports of (15)N-labeled nitrate from the tracer application in 1982 toward the hydrosphere will continue for at least another five decades. Therefore, attempts to reduce agricultural nitrate contamination of aquatic systems must consider the long-term legacy of past applications of synthetic fertilizers in agricultural systems and the nitrogen retention capacity of agricultural soils.

  14. Long-Term Effects of Manure and Inorganic Fertilizers on Yield and Soil Fertility for a Winter Wheat-Maize System in Jiangsu, China

    Institute of Scientific and Technical Information of China (English)

    JIANG Dong; H. HENGSDIJK; DAI Ting-Bo; W. de BOER; JING Qi; CAO Wei-Xing

    2006-01-01

    Winter wheat-maize rotations are dominant cropping systems on the North China Plain, where recently the use of organic manure with grain crops has almost disappeared. This could reduce soil fertility and crop productivity in the long run. A 20-year field experiment was conducted to 1) assess the effect of inorganic and organic nutrient sources on yield and yield trends of both winter wheat and maize, 2) monitor the changes in soil organic matter content under continuous wheat-maize cropping with different soil fertility management schemes, and 3) identify reasons for yield trends observed in Xuzhou City, Jiangsu Province, over a 20-year period. There were eight treatments applied to both wheat and maize seasons: a control treatment (C); three inorganic fertilizers, that is, nitrogen (N), nitrogen and phosphorus (NP), and nitrogen, phosphorus and potassium (NPK); and addition of farmyard manure (FYM) to these four treatments, that is,M, MN, MNP, and MNPK. At the end of the experiment the MN, MNP, and MNPK treatments had the highest yields,about 7 t wheat ha-1 and 7.5 t maize ha-1, with each about i t ha-1 more than the NPK treatments. Over 20 years with FYM soil organic matter increased by 80% compared to only 10% with NPK, which explained yield increases. However,from an environmental and agronomic perspective, manure application was not a superior strategy to NPK fertilizers.If manure was to be applied, though, it would be best applied to the wheat crop, which showed a better response than maize.

  15. [Humus composition and stable carbon isotope natural abundance in paddy soil under long-term fertilization].

    Science.gov (United States)

    Ma, Li; Yang, Lin-Zhang; Ci, En; Wang, Yan; Yin, Shi-Xue; Shen, Ming-Xing

    2008-09-01

    Soil samples were collected from an experimental paddy field with long-term (26 years) fertilization in Taihu Lake region of Jiangsu Province to study the effects of different fertilization on the organic carbon distribution and stable carbon isotope natural abundance (delta 13C) in the soil profile, and on the humus composition. The results showed that long-term fertilization increased the organic carbon content in top soil significantly, and there was a significantly negative exponential correlation between soil organic carbon content and soil depth (P humus (humin) was the main humus composition in the soil, occupying 50% or more, and the rest were loosely and stably combined humus. Long-term fertilization increased the content of loosely combined humus and the ratio of humic acid (HA) to fulvic acid (FA).

  16. [Variations of soil fertility level in red soil region under long-term fertilization].

    Science.gov (United States)

    Yu, Han-qing; Xu, Ming-gang; Lü, Jia-long; Bao, Yao-xian; Sun, Nan; Gao, Ju-sheng

    2010-07-01

    Based on the long-term (1982-2007) field experiment of "anthropogenic mellowing of raw soil" at the Qiyang red soil experimental station under Chinese Academy of Agricultural Sciences, and by using numerical theory, this paper studied the variations of the fertility level of granite red soil, quaternary red soil, and purple sandy shale soil under six fertilization patterns. The fertilization patterns included non-fertilization (CK), straw-returning without fertilizers (CKR), chemical fertilization (NPK), NPK plus straw-return (NPKR), rice straw application (M), and M plus straw-return (MR). The soil integrated fertility index (IFI) was significantly positively correlated with relative crop yield, and could better indicate soil fertility level. The IFI values of the three soils all were in the order of NPK, NPKR > M, MR > CK, CKR, with the highest value in treatment NPKR (0.77, 0.71, and 0.71 for granite red soil, quaternary red soil, and purple sandy shale soil, respectively). Comparing with that in the treatments of no straw-return, the IFI value in the treatments of straw return was increased by 6.72%-18.83%. A turning point of the IFI for all the three soils was observed at about 7 years of anthropogenic mellowing, and the annual increasing rate of the IFI was in the sequence of purple sandy shale soil (0.016 a(-1)) > quaternary red clay soil (0.011 a(-1)) > granite red soil (0.006 a(-1)). It was suggested that a combined application of organic and chemical fertilizers and/or straw return could be an effective and fast measure to enhance the soil fertility level in red soil region.

  17. [Effects of long-term fertilization on reddish paddy soil quality and its evaluation in a typical double-rice cropping region of China].

    Science.gov (United States)

    Nie, Jun; Yang, Zeng-Ping; Zheng, Sheng-Xian; Liao, Yu-Lin; Xie, Jian; Xiang, Yan-Wen

    2010-06-01

    In order to quantify the effects of 27 years application of chemical fertilizers, pig manure, and rice straw on the reddish paddy soil quality in double rice cropping region, the indices of soil bulk density, porosity, maximum water holding capacity, normalized mean weight diameter, pH, cation exchange capacity, available nutrients, organic matter, microbial biomass C, enzyme activities, and rice yield were selected as the evaluation indicators, and classified into four functional groups, i. e., resistance to physical degradation, plant nutrients supply and storage, resistance to biochemical degradation, and sustaining of crop productivity. The soil quality index (SQI) was calculated based on the four functional groups. The results showed that the SQI ranged from 0.544 in treatment CK to 0.729 in treatment NPK plus rice straw. Treatments PK, NP, and NK induced soil degradation, compared to treatment NPK. The deficiencies of soil P and K were the main limiting factors for the double rice productivity in reddish paddy soil area. Even though 30 t x hm(-2) x a(-1) of pig manure and 4.2 t x hm(-2) x a(-1) of rice straw were applied, the soil P and K were still not adequate for the requirement of rice growth. There was no obvious effect of long-term application of lime on the reddish paddy soil quality. The combined application of NPK with organic manure was an important and effective measure in improving soil quality in double rice cropping regions of Southern China.

  18. Climate Change and Potassium Effects Under Different N-Fertilization Input on Potato (Solanum tuberosum L.) Yield in a Long Term Field Experiment

    Science.gov (United States)

    László, Márton, ,, Dr.

    2010-05-01

    most probably through changes in the frequency of extreme climatic events. Showed that changes in variance have a greater effect on the frequency of extreme climatic events than do changes in the mean values. Hence, it is important to attempt to include changes in variability in scenarios of climate change. Potatoes are one of the most important crops in the agricultural systems of many World countries but little research in the field of climate change impact assessment has been undertaken. Potatoes are sensitives to the prevailing weather conditions (precipitation) and, hence, it is important to evaluate the effects of anthropogenic climate change on their production. The crop is demanding indicator plant of soil nutrient status too. Has a particularly high requirement for supply of soil potassium, nitrogen, phosphorus and magnesium (Johnston 2000, Kádár et al. 2000, László 2000, László et al. 2000b, 2000c, Márton 2000a, 2000b). The tubers remove 1.5 times as much potassium as nitrogen and 4 or 5 times the amount of phophate. This paper describes climate change and mainly potassium effects on potato yield on a acidic sandy brown forest soil at long term experiment scale under Mediterranean climate conditions at North- Eastern Hungary from 1962 to 1979. MATERIAL AND METHOD The effect of climatic factors, especially rainfall quantity and distribution on certain crop fertilization factors (K, N, P, Mg and potato yield) were studied in a long-term field experiment on acidic sandy brown forest soil at Nyírlugos in North- Eastern Hungary set up in 1962 and 2001. Ploughed layer of the experiment soil had a pH (KCl) 4.5, humus 0.5%, CEC 5-10 mgeq 100g-1. The topsoil was poor in all four macronutrient N, P, K and Mg. The mineral fertilization experiment involved 2 (Gülbaba and Aranyalma genotypes) x 2 (20 and 40 cm ploughed depths) x 16 (N, P, K, Mg fertilizations) = 64 treatments in 8 replications, giving a total of 512 plots. The gross and net plot sizes were 10x5

  19. Phosphorus Changes and Sorption Characteristics in a Calcareous Soil Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    GUO Sheng-Li; DANG Ting-Hui; HAO Ming-De

    2008-01-01

    Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality.The long-term (1984-1997) effects of various fertilization treatments on P changes and sorption isotherms as well as the relationship of soil properties to P sorption and P forms were evaluated in an Ustic Isohumisol,a calcareous soil,on the Loess Plateau,China.Compared to 1984,after 13 years of crop production,total soil P in the no-P treatments (control and N treatment) decreased by 5%-7%,but in the phosphorus fertilizer alone (P),nitrogen and phosphorus fertilizers in combination (NP),manure alone (M),and nitrogen and phosphorus fertilizers and manure in combination (NPM) treatments,it increased by 22%,19%,28%,and 58%,respectively.Residual fertilizer P was found mainly in NH4Ac-soluble P (Cas-P),followed by NaHCO3-sohible P (NaHCO3-P),and NH4F-soluble P (Al-P).Phosphorus sorption in the soils with different fertilization practices fit the Langmuir equations.Phosphorus sorption capacity in the no-P treatments increased,whereas it decreased in the P-included treatments (P,NP,and NPM treatments).Phosphorus sorption maximum (Qm) was significantly and negatively correlated to inorganic P including Na4CO3-P,Cas-P,NaOH-Na2CO3-soluble P (Fe-P),and AI-P (P ≤ 0.01).Moreover,long-term fertilization increased soil organic carbon in the NP,M,and NPM treatments and decreased pH in the NP and NPM treatments.Thus,the ability of the soil to release sorbed P to the environment increased under long-term P fertilization.

  20. Long-term effects of fertilization on soil organic carbon changes in continuous corn of northeast China: RothC model simulations.

    Science.gov (United States)

    Yang, X M; Zhang, X P; Fang, H J; Zhu, P; Ren, J; Wang, L C

    2003-10-01

    Soil organic C (SOC) content can increase by managing land use practices in which the rates of organic C input exceed those of organic C mineralization. Understanding the changes in SOC content of Black soils (mainly Typic Halpudoll) in northeast China is necessary for sustainable using of soil resources there. We used the RothC model to estimate SOC levels of Black soils under monoculture cropping corn in a long-term fertilization trial at Gongzhuling, Jilin Province, China. The model outputs for the changes in SOC were compared with measured data in this long-term fertilization/manure trial. The sound performance of model in simulating SOC changes suggests that RothC is feasible with Black soils in the temperate climatic region of northeast China. The modeled and measured results indicated that the treatment without fertilizer/farmyard manure (FYM) addition led to a continuous decline in SOC during the study period and N and NPK fertilization were inadequate to maintain the SOC levels in the plow layer (upper 20 cm) unless FYM was added under the current conventional management associated with no above-ground crop residues returning into the soil. Soil organic carbon could follow the same path of decline if the same management practices are maintained. Model results indicate that returning above-ground crop residues to the soil from 2002 to 2022 would increase SOC by 26% for the treatment without fertilization addition, 40% for N treatment, 45% for NPK treatment, and 38% and 46% for N and NPK treatments with FYM addition, compared to the levels in the corresponding treatments in 2002. The simulation results suggest that the RothC model is a feasible tool to assess SOC trend under different management practices, and returning above-ground crop residues into the soil would lead to a remarkable increase in SOC of Black soils in the region.

  1. Differences in chemical composition of soil organic carbon resulting from long-term fertilization strategies.

    Science.gov (United States)

    Li, Zengqiang; Zhao, Bingzi; Wang, Qingyun; Cao, Xiaoyan; Zhang, Jiabao

    2015-01-01

    Chemical composition of soil organic carbon (SOC) is central to soil fertility. We hypothesize that change in SOC content resulting from various long-term fertilization strategies accompanies the shift in SOC chemical structure. This study examined the effect of fertilization strategies along with the time of fertilizer application on the SOC composition by 13C nuclear magnetic resonance (NMR) spectroscopy. The soils (Aquic Inceptisol) subjected to seven fertilizer treatments were collected in 1989, 1999 and 2009, representing 0, 10 and 20 years of fertilization, respectively. The seven fertilizer treatments were (1-3) balanced fertilization with application of nitrogen (N), phosphorus (P) and potassium (K) including organic compost (OM), half organic compost plus half chemical fertilizer (1/2OM), and pure chemical NPK fertilizer (NPK); (4-6) unbalanced chemical fertilization without application of one of the major elements including NP fertilizer (NP), PK fertilizer (PK), and NK fertilizer (NK); and (7) an unamended control (CK). The SOC content in the balanced fertilization treatments were 2.3-52.6% and 9.4-64.6% higher than in the unbalanced fertilization/CK treatments in 1999 and 2009, respectively, indicating significant differences in SOC content with time of fertilizer application between the two treatment groups. There was a significantly greater proportion of O-alkyl C and a lower proportion of aromatic C in the balanced fertilization than in unbalanced fertilization/CK treatments in 1999, but not in 2009, because their proportions in the former treatments approached the latter in 2009. Principal component analysis further showed that the C functional groups from various fertilization strategies tended to become compositionally similar with time. The results suggest that a shift in SOC chemical composition may be firstly dominated by fertilization strategies, followed by fertilization duration.

  2. Phosphorus speciation of clay fractions from long-term fertility experiments in Sweden

    OpenAIRE

    Eriksson, Ann Kristin; Gustafsson, Jon Petter; Hesterberg, Dean

    2015-01-01

    Phosphorus (P) losses from agricultural soils constitute a main driver for eutrophication of the Baltic Sea. There is limited knowledge about sorption and release processes of P in these soils, especially concerning the effects of fertilization. In this study, P speciation of the clay fractions from six different soils in long-term fertility experiments in Sweden was investigated by P K-edge XANES spectroscopy. As expected, unfertilized soils had lower concentrations of acid-digestible P comp...

  3. Effects of 42-year long-term fertilizer management on soil phosphorus availability, fractionation,adsorption–desorption isotherm and plant uptake in flooded tropical rice

    Institute of Scientific and Technical Information of China (English)

    Pratap; Bhattacharyya; Amaresh; Kumar; Nayak; Mohammad; Shahid; Rahul; Tripathi; Sangita; Mohanty; Anjani; Kumar; Rajagounder; Raja; Bipin; Bihari; Panda; Banwari; Lal; Priyanka; Gautam; Chinmaya; Kumar; Swain; Koushik; Singha; Roy; Pradeep; Kumar; Dash

    2015-01-01

    Soil phosphorus(P) fractionation, adsorption, and desorption isotherm, and rice yield and P uptake were investigated in flooded tropical rice(Oryza sativa L.) following 42-year fertilizer and manure application. The treatments included low-input [unfertilized control without N, P, or K(C0N0)], farmyard manure(FYM)(C1N0), NP(C0NP), NPK(C0NPK), FYM + NP(C1NP), and high-input treatment, FYM + NPK(C1NPK). Grain yield was increased significantly by 74%over the control under the combined application of FYM + NPK. However, under low- and high-input treatments, yield as well as P uptake was maintained at constant levels for 35 years.During the same period, high yield levels and P uptake were maintained under the C0 NP, C0 NPK,and C1 NPK treatments. These are unique characteristics of a tropical flooded ecosystem, which is a self-sustaining system for rice production. The Fe–P fraction was highest compared to the Ca–P and Al–P fractions after 42 years of fertilizer application and was significantly higher under FYM + NPK treatment. The P adsorption capacity of soil was highest under the low-input treatment and lowest under long-term balanced fertilization(FYM + NPK). In contrast, P desorption capacity was highest under NPK and lowest in the control treatment. Long-term balanced fertilization in the form of FYM + NPK for 42 years lowered the bonding energy and adsorption capacity for P in soil but increased its desorption potential, increasing P availability to the plant and leading to higher P uptake and yield maintenance.

  4. Modeling some long-term implications of CO2 fertilization for global forests and forest industries

    Science.gov (United States)

    Joseph Buongiorno

    2015-01-01

    Background: This paper explored the long-term, ceteris-paribus effects of potential CO2 fertilization on the globalforest sector. Based on the findings of Norby et al. (PNAS 2005, 102(50)) about forest response to elevated [CO2].Methods:...

  5. Impact of Long-Term Fertilization on Cropland Soil Fauna Community at Loess Soil, Shannxi, China

    Institute of Scientific and Technical Information of China (English)

    LIN Ying-hua; YANG Xue-yun; ZHANG Fu-dao; GU Qiao-zhen; SUN Ben-hua; MA Lu-jun

    2005-01-01

    The relationship between long-term fertilization and cropland soil fauna was studied at the station's experiment research network for soil fertility and fertilizers in Loess soil of Shannxi Provincefrom Jul. 2001 to Oct. 2002. Six types of long-term fertilizer were carried out for this study including non-fertilizer (CK), abandonment (ABAND), nitrogenous and phosphors and potassium fertilizers combined (NPK), straw and NPK (SNPK), organic material and NPK (MNPK) and 1.5 times MNPK (1.5MNPK). 72 soil samples were collected and 5 495 species of cropland soil fauna obtained by handsorting and Cobb methods at 4 times, belonging to 6 Phyla, 11 Classes, 22 Orders, 2 Superfamilies, 61 Families and 35 Genera. The result showed that different fertilizer had significantly impacted on the cropland soil fauna (F = 2.24, P<0.007). The number of the cropland soil fauna was related to the soil physicochemical properties caused by long-term fertilization. The result by principal component analysis, focusing on the number of 15 key soil fauna species group's diversity, evenness of community and the total soil fauna individuals indicated that the effects of SNPK, NPK, MNPK and 1.5MNPK were significantly different from that of the cropland soil fauna, in which, SNPK and NPK had the positive effect on cropland soil fauna, and MNPK and 1.5 MNPK had the negative affect, others could not be explained. By principal component I,the synthetic effect of different fertilization on the total soil fauna individuals and the group was most significant, and the effect was little on evenness and diversity. By value of eigenvectors, the maximum one was 9.6248, and the minimum one was -1.0904, that means the 6 types of fertilization did not affect evenly the cropland soil fauna.

  6. Long-term effects of mineral and organic fertilization on soil organic matter fractions and sorghum yield under Sudano-Sahelian conditions

    NARCIS (Netherlands)

    Mando, A.; Bonzi, M.; Wopereis, M.C.S.; Lompo, F.; Stroosnijder, L.

    2005-01-01

    Knowledge of changes in soil organic matter (SOM) fractions resulting from agricultural practice is important for decision-making at farm level because of the contrasting effects of different SOM fractions on soils. A long-term trial sited under Sudano-Sahelian conditions was used to assess the effe

  7. Effects of long-term fertilization on soil fungi%长期施肥对农田土壤真菌的影响

    Institute of Scientific and Technical Information of China (English)

    王轶; 李季; 曹志平; 杨合法

    2014-01-01

    不合理施肥所引发的土壤环境问题逐渐成为制约我国农业可持续发展的重要因素之一,而土壤真菌作为一类重要的土壤微生物,研究施肥措施对真菌群落的影响对促进农业生产具有重要意义。本研究以有20年历史的长期定位试验田为研究对象,利用末端限制性片段长度多态性分析技术,对长期定位施肥农田生态系统中不同施肥方式对土壤真菌群落的影响以及时间变化规律进行了系统研究。长期施肥定位试验包括 EM堆肥(EM)、传统堆肥(OF)、化肥(CF)和不施肥(CK)处理。主要研究结果如下:在0~20 cm土层,施肥处理对土壤真菌多样性有显著影响, Shannon-Weiner多样性指数为2.64~3.53, Simpson集中性指数为0.03~0.08; EM和OF处理的Shannon-Weiner多样性指数均显著高于CF和CK;在3月、6月和10月, EM和OF处理与CF和CK处理相比,有较高的真菌多样性;Simpson集中性指数最高的是3月的CK处理,最低的是10月的EM和OF 处理。冗余分析结果表明,土壤 pH、有机质、总氮、有效磷和有效钾等对真菌影响显著。因此,长期施用有机肥与化肥相比可以提高土壤真菌多样性,改变其群落结构;与化肥处理相比,施用EM堆肥,不仅可以保持土壤可持续利用性,同时改善0~20 cm土层土壤真菌的生存环境;3种施肥处理对土壤真菌群落结构影响程度由强到弱:EM>OF>CF。%Fungi are critical for the decomposition of terrestrial organic matter and subsequent global carbon cycle. High microbial diversity is essential for efficient nutrient recycling in soils. To investigate the impacts of different application modes of fertilizers on fungal communities, a long-term fertilization experiment (of over 20 years of continuous fertilizer treatments) was conducted in North China. Soil samples were collected from 4 treatments: effective microorganisms compost (EM), traditional compost (OF), chemical fertilizer (CF

  8. 长期施肥对农田土壤氮素关键转化过程的影响%Effects of Long-term Fertilization on Key Processes of Soil Nitrogen Cycling in Agricultural Soil:A Review

    Institute of Scientific and Technical Information of China (English)

    王敬; 程谊; 蔡祖聪; 张金波

    2016-01-01

    fertilizer in the future. Therefore,optimal N fertilizer management strategies synchronizing N supply with crop demand should be developed to maintain crop yield and economic profit while minimizing negative environmental impact. Organic fertilizer as substitute for mineral N fertilizer has been advocated and practiced to increase soil carbon(C)sequestration and improve soil fertility. It has also been suggested that application of organic fertilizers,either alone or in combination with mineral N fertilizers,is effective in mitigating N-related pollution,improving soil fertility,and increasing crop yield. At present,how to fertilize rationally,improve crop yields,build up soil fertility and meanwhile maintain a sound ecological environment is one of the major challenges to agricultural research. Which step of N transformation in the soil would long-term application of organic manure affect thus influencing N supplying capacity and N retaining mechanism of the soil? What is the mechanism behind long-term application of organic manure decreasing N-related pollution and the increasing crop yield? This review elaborated effects of long-term fertilization on key processes of soil nitrogen cycling in agricultural soil in expectation to provide some theoretical basis for rationalization of long-term fertilization and improvement of N fertilizer utilization rate. The review proceeded from the angle of primary N transformation rate of the processes of soil nitrogen cycling to discuss effects of fertilization(mineral or organic fertilizers)on key processes of the soil nitrogen cycling. Soil N mineralization and assimilation are two crucial links in the cycling and factors that determine soil N supplying capacity. Long term application of nitrogen fertilizers could increase soil organic N and C contents and provide crops with available N slowly through mineralization of soil organic N and subsequent nitrification. Large volumes of long-term fertilization experiments demonstrate that

  9. Long-term manure incorporation with chemical fertilizers reduced environmental nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization in intensive farming systems are essential for sustainable agriculture and food security around the world. The objective of this study was to determine the long-term effects of various fertilization...

  10. Long Term Transfer Effect of Metaphoric Allusion.

    Science.gov (United States)

    Hayes, David A.; Mateja, John A.

    A study was conducted to investigate the long term transfer effect of metaphoric allusion used to clarify unfamiliar subject matter. Forty-nine high school students were given unfamiliar prose materials variously augmented by metaphoric allusion. The subjects' immediate performance on a transfer task was compared to their performance on an…

  11. 长期间作牧草对椰园土壤肥力的影响%Effects of Long-term Intercropping Pastures on Coconut Soil Fertility

    Institute of Scientific and Technical Information of China (English)

    王萍; 刘立云; 杨伟波; 陈思婷; 唐龙祥; 王东劲; 周汉林; 郇树乾

    2011-01-01

    After long-term intercropping pastures in young coconut grove for 10 years, the soil pH of 0 -20 cm decreased 0.92 unit, the 20 - 40 cm decreased 0.75 unit, and in old coconut grove the soil pH of 0 - 20 cm decreased 0.82 unit, the 20 - 40 cm decreased 1.04 unit; after long-term intercropping pastures in young coconut grove for 10 years, the soil water content was lower than before, but higher than before , in old coconut grove the soil water content decreased above half than before and was lower compared with the young coconut grove; after long-term intercropping pastures in young coconut grove for 10 years, the soil organic matter of 0 -20 cm was higher than before, but the 20 -40 cm was lower, and in old coconut grove there were all lower; after long-term intercropping pastures in young coconut grove for 10 years, the soil total nitrogen content was a little lower than before, but in old coconut grove it decreased above half than before, but was higher compared with the young coconut grove. These results suggesed that long-term intercropping pastures in coconut grove, there must be applying fertilizer properly, and combining with proper lime or adopting legume-graminaceae rotation or legume-non graminaceae rotation.%幼龄椰园长期间作牧草,10年后0~20 cm层下降0.92个pH单位,20~40cm层下降0.75个单位,而成龄椰园0~20 cm层下降0.82个单位,20~40 cm层下降1.04个单位;幼龄椰园间作牧草,10年后土壤含水量有所下降,但仍比间作前高,而成龄椰园土壤含水量下降了一半以上,而且比幼龄椰园低;幼龄椰园间作牧草,10年后0~20 cm土层有机质含量比间作前有所上升,但20~40cm以下则低于间作前,成龄椰园均比间作前明显降低;幼龄椰园间作牧草,10年后土壤全氮含量略微降低,而成龄椰园下降了一半以上,但目前成龄椰园的土壤全氮含量比幼龄椰园的略高.建议椰园实行长期牧草间作,每年必须追施足够的肥料,并

  12. The Changes in Guilin Paddy Soil Organic Matter and Rice Yield under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    Qiuliang YU; Zheng TANG; Zhongfang LI; Chunlan CHEN; Xiaoxian TANG; Yanli LIN

    2016-01-01

    Rational fertilization is an important measure to increase crop yield and soil fertility. Through analysis,this paper aims to master the change characteristics of soil organic matter and rice yield under different fertilizer treatments,in order to provide an important reference for the sustainable use of soil and effective fertilization. Long-term( 19 years) rice crop rotation experiments in waterloggogenic paddy soil were conducted to investigate the change trend of crop grain yield and soil organic matter with time,reveal the dynamic characteristics and relationship between main fertility factors and crop yields using comparative analysis at three sites with conventional fertilization and non-fertilization in Guilin. The results showed that compared with previous years,the rice yield increased by 53% under the fertilization treatment and degreased by 66% under the control. Over the years,the average soil organic matter( SOM) content under fertilization treatment was 23% higher than under CK treatment. This indicates that chemical fertilizer and organic manure application can increase the rice yield and soil organic matter,and high rice yield can be attributed to the SOM increase.

  13. Potential for Local Fertilization: A Benthocosm Test of Long-Term and Short-Term Effects of Mussel Excretion on the Plankton.

    Science.gov (United States)

    Cherif, Mehdi; Granados, Monica; Duffy, Sean; Robert, Pauline; Péquin, Bérangère; Mohit, Vani; McKindsey, Christopher W; Archambault, Philippe; Myrand, Bruno; Lovejoy, Connie; Tremblay, Réjean; Plourde, Stéphane; Fussmann, Gregor F

    2016-01-01

    Mussel aquaculture has expanded worldwide and it is important to assess its impact on the water column and the planktonic food web to determine the sustainability of farming practices. Mussel farming may affect the planktonic food web indirectly by excreting bioavailable nutrients in the water column (a short-term effect) or by increasing nutrient effluxes from biodeposit-enriched sediments (a long-term effect). We tested both of these indirect effects in a lagoon by using plankton-enclosing benthocosms that were placed on the bottom of a shallow lagoon either inside of a mussel farm or at reference sites with no history of aquaculture. At each site, half of the benthocosms were enriched with seawater that had held mussels (excretion treatment), the other half received non-enriched seawater as a control treatment. We monitored nutrients ([PO43-] and [NH4+]), dissolved oxygen and plankton components (bacteria, the phytoplankton and the zooplankton) over 5 days. We found a significant relationship between long-term accumulation of mussel biodeposits in sediments, water-column nutrient concentrations and plankton growth. Effects of mussel excretion were not detected, too weak to be significant given the spatial and temporal variability observed in the lagoon. Effects of mussels on the water column are thus likely to be coupled to benthic processes in such semi-enclosed water bodies.

  14. Potential for Local Fertilization: A Benthocosm Test of Long-Term and Short-Term Effects of Mussel Excretion on the Plankton.

    Directory of Open Access Journals (Sweden)

    Mehdi Cherif

    Full Text Available Mussel aquaculture has expanded worldwide and it is important to assess its impact on the water column and the planktonic food web to determine the sustainability of farming practices. Mussel farming may affect the planktonic food web indirectly by excreting bioavailable nutrients in the water column (a short-term effect or by increasing nutrient effluxes from biodeposit-enriched sediments (a long-term effect. We tested both of these indirect effects in a lagoon by using plankton-enclosing benthocosms that were placed on the bottom of a shallow lagoon either inside of a mussel farm or at reference sites with no history of aquaculture. At each site, half of the benthocosms were enriched with seawater that had held mussels (excretion treatment, the other half received non-enriched seawater as a control treatment. We monitored nutrients ([PO43-] and [NH4+], dissolved oxygen and plankton components (bacteria, the phytoplankton and the zooplankton over 5 days. We found a significant relationship between long-term accumulation of mussel biodeposits in sediments, water-column nutrient concentrations and plankton growth. Effects of mussel excretion were not detected, too weak to be significant given the spatial and temporal variability observed in the lagoon. Effects of mussels on the water column are thus likely to be coupled to benthic processes in such semi-enclosed water bodies.

  15. Effects of long-term fertilizer on soil fertility and soil enzyme activities in upland red soils%长期施肥对旱地红壤肥力和酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    邵兴华; 徐金仁; 张建忠; 李海峰; 周同林; 张辉

    2011-01-01

    In order to understand the relation between soil enzyme activity and soil chemical propertities in upland red soil under different fertilizer treatments, we conducted a study to determine the effects of pig manure, inorganic fertiliser and combination of pig manure and inorganic NPK on soil chemical and biological properties in a more than 30 a long-term fertilization experiment. The treatments as the following: no fertilization(CK), N, NP, NPK, double NPK, pig manure, NPK+pig manure. The results showed, the total N content had no significant difference between different treatments. The only applied N could significantly improve available N in soil. Soil pH, organic matter, total P and available P in manure fertilization treatments ( NPK+pig manure and pig manure) all increased significantly compared with no fertilization (CK) and mineral fertilization treatmets (N, NP, NPK and double NPK). Except for the highest urease activity was double NPK treatment, the soil invertase, dehydrognease, catalase and acid phosphatase activities were all significantly higher than those in other fertilization treatments. Acid phosphatase, catalase, dehydrognease and urease activities were significant and dramatically significant positively correlated with total N, organic matter and available N. So, manure application or co-application of manure and mineral fertilizers not only increased the soil fertility, but also enhanced significantly soil enzymes activities, thus could improve red soil sustainable productivity.%为了明确不同施肥种类对旱地红壤肥力与酶活性的影响,以30年(1981年至今)长期定位试验地为基础,研究不同施肥处理(CK,N,NP,NPK,2倍NPK,猪粪,NPK+猪粪)旱地红壤玉米田耕层(0~20 cm)土壤酶活性与养分的变化趋势及其相关性.结果表明:1)全N含量各处理间差异不显著,单施N肥显著增加土壤速效N,施有机肥处理(NPK+猪粪,猪粪)土壤的pH值、有机质、全P、速效P均显著增加;2)

  16. Short-term effects of fertilization on photosynthesis and leaf morphology of field-grown loblolly pine following long-term exposure to elevated CO2 concentration

    Science.gov (United States)

    Chris A. Maier; Sari Palmroth; Eric Ward

    2008-01-01

    We examined effects of a first nitrogen (N) fertilizer application on upper-canopy needle morphology and gas exchange in ~20-m-tall loblolly pine (Pinus taeda L.) exposed to elevated carbon dioxide concentration ([CO2]) for 9 years. Duke Forest free-air CO2 enrichment (FACE) plots were split and half of...

  17. Effects of Long Term Application of Inorganic and Organic Fertilizers on Soil Organic Carbon and Physical Properties in Maize–Wheat Rotation

    Directory of Open Access Journals (Sweden)

    Babbu Singh Brar

    2015-06-01

    Full Text Available Balanced and integrated use of organic and inorganic fertilizers may enhance the accumulation of soil organic matter and improves soil physical properties. A field experiment having randomized complete block design with four replications was conducted for 36 years at Punjab Agricultural University (PAU, Ludhiana, India to assess the effects of inorganic fertilizers and farmyard manure (FYM on soil organic carbon (SOC, soil physical properties and crop yields in a maize (Zea mays–wheat (Triticum aestivum rotation. Soil fertility management treatments included were non-treated control, 100% N, 50% NPK, 100% NP, 100% NPK, 150% NPK, 100% NPK + Zn, 100% NPK + W, 100% NPK (-S and 100% NPK + FYM. Soil pH, bulk density (BD, electrical conductivity (EC, cation exchange capacity, aggregate mean weight diameter (MWD and infiltration were measured 36 years after the initiation of experiment. Cumulative infiltration, infiltration rate and aggregate MWD were greater with integrated use of FYM along with 100% NPK compared to non-treated control. No significant differences were obtained among fertilizer treatments for BD and EC. The SOC pool was the lowest in control at 7.3 Mg ha−1 and increased to 11.6 Mg ha−1 with 100%NPK+FYM. Improved soil physical conditions and increase in SOC resulted in higher maize and wheat yields. Infiltration rate, aggregate MWD and crop yields were positively correlated with SOC. Continuous cropping and integrated use of organic and inorganic fertilizers increased soil C sequestration and crop yields. Balanced application of NPK fertilizers with FYM was best option for higher crop yields in maize–wheat rotation.

  18. Long-term effects of sibling incest.

    Science.gov (United States)

    Daie, N; Witztum, E; Eleff, M

    1989-11-01

    Although sexual abuse of children is recognized as a serious problem, sibling incest has received relatively little attention. A distinction has been made between power-oriented sibling incest and nurturance-oriented incest. The authors review the relevant literature and present four clinical examples. The cases illustrate the broad range of sibling incest and demonstrate its effects, including the long-term consequences for the perpetrator. Lasting difficulties in establishing and maintaining close relationships, especially sexual ones, are prominent features of each case. Without denying the occurrences of benign sex-play between siblings, the authors emphasize exploitation and abuse as pathogenic aspects of sibling incest.

  19. Long term effects of Escherichia coli mastitis.

    Science.gov (United States)

    Blum, Shlomo E; Heller, Elimelech D; Leitner, Gabriel

    2014-07-01

    Escherichia coli is one of the most frequently diagnosed causes of bovine mastitis, and is typically associated with acute, clinical mastitis. The objective of the present study was to evaluate the long term effects of intramammary infections by E. coli on milk yield and quality, especially milk coagulation. Twenty-four Israeli Holstein cows diagnosed with clinical mastitis due to intramammary infection by E. coli were used in this study. Mean lactation number, days in milk (DIM) and daily milk yield (DMY) at the time of infection was 3.3 ± 1.3, 131.7 days ± 78.6 and 45.7 L ± 8.4, respectively. DMY, milk constituents, somatic cells count (SCC), differential leukocytes count and coagulation parameters were subsequently assessed. Two patterns of inflammation were identified: 'short inflammation', characterized by 15% decrease in DMY and >30 days to reach a new maximum DMY (n = 19). The estimated mean loss of marketable milk during the study was 200 L/cow for 'short inflammation' cases, and 1,500 L/cow for 'long inflammation' ones. Significant differences between 'short' and 'long inflammation' effects were found in almost all parameters studied. Long-term detrimental effects on milk quality were found regardless of clinical or bacteriological cure of affected glands.

  20. Effects of Long-term Located Fertilization on the Physiochemical Properties of Non-calcareous Alluvial Soil%长期定位施肥对无石灰性潮土理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    赵秀芬; 李俊良

    2009-01-01

    [目的]为改善土壤理化性质和促进农业可持续发展提供理论依据.[方法]通过田间试验研究长期定位不同施肥对无石灰性潮土理化性质的影响.[结果]单施有机肥处理的土壤含水量最高,CK的土壤含水量最低.施用有机肥处理的土壤容重较小,CK和无机肥处理的土壤容重较大.施用有机肥处理的土壤孔隙度显著高于不施有机肥处理和CK.施用有机肥、化肥处理和CK的土壤有机质含量分别约为原始土样的7.5、2.8和2.3倍.施用有机肥处理的土壤pH值提高了0.62,施用无机肥处理的土壤pH值降低.长期定位不同施肥对土壤速效养分氮磷钾含量的影响为:有机-无机肥料配施>单施大量有机肥>无机肥配施>单施氮肥>不施肥.[结论]有机-无机肥料配施能有效改善无石灰性潮土的理化性质.%[Objective]The purpose of the research was to supply theoretical basis for improving the physiochemical properties of soil and promoting agricultural sustainable development. [Method]The effects of applying different fertilizers in long-term located fertilization on the physiochemical properties of non-calcareous alluvial soil were researched through field experiment. [Result]The soil water content in the treatment with organic fertilizer only was highest and that in CK was lowest. The soil buil density in the treatment with organic fertilizer was smaller and that in CK and the treatment with inorganic fertilizer were bigger. The soil porosity in the treatment with organic fertilizer was significantly higher than that in the treatment without organic fertilizer and CK. The soil organic matter contents in the treatments with organic fertilizer, chemical fertilizer and CK were about 7.5, 2.8 and 2.3 times of that in the original soil samples resp. The soil pH value in the treatment with organic fertilizer was enhanced by 0.62 and that in the treatment with inorganic fertilizer was decreased. The effects of

  1. Nitrogen uptake during one year in subarctic plant functional groups and in microbes after long-term warming and fertilization

    DEFF Research Database (Denmark)

    Sørensen, Pernille Lærkedal; Michelsen, Anders; Jonasson, Sven Evert

    2008-01-01

    For the first time in an arctic long-term warming and fertilization experiment, the short-term (days) and longer-term (month and year) nitrogen (N) uptake and allocation in plants, microbes, and soil pools were studied, with 15N-labeling of an organic nitrogen form, glycine. The long-term warming...... and fertilization had no marked effect on soil inorganic N content, but both dissolved organic N (DON) and plant biomass did increase after fertilization. Soil microbes initially immobilized most of the added 15N, but in the following months, they lost two-thirds, while label concentration in plants increased....... After a year, however, the 15N recovered in microbes was still 10-fold higher than that in the plant biomass, showing the high importance of soil microbes in nutrient retention in arctic ecosystems, irrespective of the impact of long-term warming or fertilization. The effects of the treatments...

  2. [Effects of long-term mixed application of organic and inorganic fertilizers on canopy apparent photosynthesis and yield of winter wheat].

    Science.gov (United States)

    Zhao, Jun; Dong, Shu-ting; Liu, Peng; Zhang, Ji-wang; Zhao, Bin

    2015-08-01

    A field experiment was conducted using the winter wheat (Triticum aestivum) variety Shimai 15. The source of organic nitrogen was cow manure, and four fertilization treatments were included, i.e., no N fertilizer application, single application of urea, single application of cow manure, and mixed application of urea and cow manure. The effects of different applications of inorganic and organic nitrogen on canopy apparent photosynthesis (CAP), photosynthetic rate of flag leaves (Pn), leaf area index (LAI), florescence parameters and grain yield of winter wheat were determined. The results showed that urea had the largest effect on the early growth period, as at this stage the CAP, Pn and LAI of the single application of urea were the highest, which was followed by the mixed application and the single application of cow manure. However, 10 days after anthesis, the single application of cow manure and the mixed application delayed the leaf senescence process when compared with the single application of urea. This could be due to the two treatments having higher anti-oxidant enzyme activity and promoting a longer green leaf duration, which could maintain a higher photosynthetic capability. What' s more, the mixed application had a better performance and got the highest grain yield. Consequently, the mixed application of organic and inorganic fertilizers could delay leaf senescence and maintain a better canopy structure and higher photosynthesis capability at the late grain filling stage, which resulted in a higher grain yield.

  3. Modeling some long-term implications of CO2 fertilization for global forests and forest industries

    Institute of Scientific and Technical Information of China (English)

    Joseph; Buongiorno

    2016-01-01

    Background:This paper explored the long-term, ceteris-paribus effects of potential CO2 fertilization on the global forest sector. Based on the findings of Norby et al. (PNAS 2005, 102(50)) about forest response to elevated [CO2]. Methods:Forest productivity was increased in the Global Forest Products Model (GFPM) in proportion to the rising [CO2] projected in the IPCC scenario A1B, A2, and B2. Projections of the forest area and forest stock and of the production, consumption, prices, and trade of products ranging from fuelwood to paper and paperboard were obtained with the GFPM for each scenario, with and without CO2 fertilization beginning in 2011 and up to 2065. Results:CO2 fertilization increased wood supply, leading to lower wood prices which in turn induced modest lower prices of end products and higher global consumption. However, production and value added in industries decreased in some regions due to the relative competitive advantages and to the varying regional effects of CO2 fertilization. Conclusion:The main effect of CO2 fertilization was to raise the level of the world forest stock in 2065 by 9 to 10%for scenarios A2 and B2 and by 20%for scenario A1B. The rise in forest stock induced by fertilization was in part counteracted by its stimulation of the wood supply which resulted in lower wood prices and increased harvests.

  4. 长期施肥对薄层黑土酶活性及土壤肥力的影响%Effect of long-term fertilization on enzyme activities and soit fertility in the black thin-layer soil

    Institute of Scientific and Technical Information of China (English)

    焦晓光; 隋跃宇; 魏丹

    2011-01-01

    Soil enzyme activities and soil fertility were studied to explore the long-term fertilization on soil enzyme activities and its relationship with soil fertility on the basis of 29-years long-term site-specific experiment with different fertilization methods. The results showed that combined application of chemical fertilizers and organic manure could significantly increase the soil organic matter, total nitrogen, total phosphorus, alkali-soluble nitrogen, available phosphorus content and enhance the soil urease, phosphatase, invertase, catalase, dehydrogenase activity. The results of correlation analysis showed that soil urease, phosphatase, invertase catalase and dehydrogenase activity positively corrected with organic matter, total nitrogen, total phosphorus and alkali-soluble nitrogen significantly, and the integrated activities of soil urease, phosphatase, invertase, catalase dehydrogenase activity could reflect the changing trend of black thin-layer soil quality in the farmland after long-term fertilization.%利用29年的长期定位试验,对不同的施肥方式下薄层黑土酶活性及肥力进行了研究,探讨长期施肥对土壤酶活性及与土壤肥力的影响.结果表明,化肥与有机肥配合施用能明显提高土壤有机质、全氮、全磷、碱解氮、有效磷含量,增强土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶活性.相关分析结果显示,土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶活性与有机质、全氮、全磷、有效磷、碱解氮呈显著正相关.土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶综合活性可以反映长期施肥后薄层黑土质量的变化趋势.

  5. Influence of long-term fertilization on soil enzyme activities

    Directory of Open Access Journals (Sweden)

    Alina Dora SAMUEL

    2009-05-01

    Full Text Available Soil enzyme activities (actual and potential dehydrogenase, catalase, acid and alkaline phosphatase were determined in the 0–10, 10–20, and 20–30 cm layers of a brown luvic soil submitted to a complex fertilization experiment with different types of green manure. It was found that each activity decreased with increasing sampling depth. It should be emphasized that greenmanuring of maize led to a significant increase in each of the five enzymatic activities determined. The enzymatic indicators of soil quality calculated from the values of enzymatic activities showed the order: lupinus + rape + oat > lupinus > vetch + oat + ryegrass > lupinus + oat + vetch > unfertilized plot. This order means that by determination of enzymatic activities valuable information can be obtained regarding fertility status of soils. There were significant correlations of soil enzyme activities with chemical properties.

  6. Long term hypolipidaemic and anti-atherogenic effects of Carica ...

    African Journals Online (AJOL)

    Long term hypolipidaemic and anti-atherogenic effects of Carica papaya Linn. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... This study was designed to assess the long term (24 weeks) effects of daily oral ...

  7. Long-term fertilization modifies the structures of soil fulvic acids and their binding capability with Al.

    Science.gov (United States)

    Wu, Jun; Wu, Minjie; Li, Chunping; Yu, Guanghui

    2014-01-01

    The binding characteristics of organic ligands and minerals in fulvic acids (FAs) with Al are essential for understanding soil C sequestration, remain poorly understood. In this study, Fourier transform infrared (FTIR) spectroscopy combined with two-dimensional correlation spectroscopy (2DCOS) analysis was applied for the first time to explore the binding of Al with organic ligands and minerals in soil FAs. For these analyses, two contrasting treatments were selected from a long-term (i.e., 22-year) fertilization experiment: chemical (NPK) fertilization and swine manure (SM) fertilization. The results showed that the long-term application of organic and inorganic fertilizers to soils had little effect on the compositions of the fluorescent substances and organic ligands in the soil FAs. However, long-term SM fertilization increased the weathered Al and Si concentrations in the soil FAs compared with long-term chemical fertilization. Furthermore, organic ligands in the soil FAs were mainly bound with Al in the NPK treatment, whereas both organic ligands and minerals (Al-O-Si, Si-O) were bound with Al under the M fertilization conditions. Both transmission electron microscopy (TEM) images and X-ray diffraction spectra demonstrated that amorphous and short-range-ordered nanominerals were abundant in the soil FAs from the SM plot in contrast to the soil FAs from the NPK plot. This result illustrates the role nanominerals play in the preservation of soil FAs by during long-term organic fertilization. In summary, the combination of FTIR and 2D correlation spectroscopy is a promising approach for the characterization of the binding capability between soil FAs and Al, and a better understanding FA-Al binding capability will greatly contribute to global C cycling.

  8. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0–20, 20–40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ13C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0–20 cm = 1492.4 gC m2 and 20–40 cm = 1770.6 gC m2) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  9. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses.

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ(13)C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m(2) and 20-40 cm = 1770.6 gC m(2)) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  10. Long-term fertilization alters the relative importance of nitrate reduction pathways in salt marsh sediments

    Science.gov (United States)

    Peng, Xuefeng; Ji, Qixing; Angell, John H.; Kearns, Patrick J.; Yang, Hannah J.; Bowen, Jennifer L.; Ward, Bess B.

    2016-08-01

    Salt marshes provide numerous valuable ecological services. In particular, nitrogen (N) removal in salt marsh sediments alleviates N loading to the coastal ocean. N removal reduces the threat of eutrophication caused by increased N inputs from anthropogenic sources. It is unclear, however, whether chronic nutrient overenrichment alters the capacity of salt marshes to remove anthropogenic N. To assess the effect of nutrient enrichment on N cycling in salt marsh sediments, we examined important N cycle pathways in experimental fertilization plots in a New England salt marsh. We determined rates of nitrification, denitrification, and dissimilatory nitrate reduction to ammonium (DNRA) using sediment slurry incubations with 15N labeled ammonium or nitrate tracers under oxic headspace (20% oxygen/80% helium). Nitrification and denitrification rates were more than tenfold higher in fertilized plots compared to control plots. By contrast, DNRA, which retains N in the system, was high in control plots but not detected in fertilized plots. The relative contribution of DNRA to total nitrate reduction largely depends on the carbon/nitrate ratio in the sediment. These results suggest that long-term fertilization shifts N cycling in salt marsh sediments from predominantly retention to removal.

  11. SOIL AGROCHEMICAL PROPERTIES IMPROVEMENT IN LONG TERM FIELD EXPERIMENT WITH FERTILIZERS

    Directory of Open Access Journals (Sweden)

    Mihaela Lungu

    2005-10-01

    Full Text Available Soil fertility is studied in long-term field experiments. Researches are carried out in several agricultural research stations, out of which the following have been chosen for the present paper: Albic Luvisol* at Albota; Haplic Phaeozem at Fundulea; Chromic Luvisol at Şimnic; Calcic Chernozem at Secuieni; and Haplic Chernozem at Podu Iloaiei. Long term fertilization with nitrogen and phosphorus generally improved the soil agrochemical properties. The evolution of organic matter, nitrogen, mobile phosphorus and potassium, and mobile microelements contents were studied, using the standardized method used in the ICPA laboratories. The organic matter and total nitrogen contents didn’t change significantly under the nitrogen and phosphorus long-term fertilization influence. The mobile phosphorus contents have the tendency to grow very significantly with the growth of phosphorus fertilizers. At the same time, slight depletions of these contents are registered as the high nitrogen doses from fertilizers stimulate plant growth and, obviously, nutritive elements absorption. Mobile potassium contents changes very little, with insignificant differences. Significant depletions are registered only with high fertilizers doses, due to the stimulation of the nutritive elements absorption in plants. Microelements contents don’t change almost at all. They are within the normal content limits and no excess or deficiency was registered, in any of the studied stations. For the agricultural practice, economical studies are recommended, about how high fertilizing expenses are covered by the yield growth. Not the least, production quality study in different variants of mineral fertilization could prove interesting.

  12. Effects of Long-term Fertilization on Phosphorus Supply Capacity and Availability in Black Soil%长期施肥对黑土供磷能力及磷素有效性的影响

    Institute of Scientific and Technical Information of China (English)

    陈欣; 韩晓增; 宋春; 梁尧; 丁雪丽

    2012-01-01

    [Objective] The research aimed to study the effects of long-term fertilization on phosphorus supply capacity, phosphorus fractions transformation in black soil. [Method] The soil samples of pot experiment were collected from a long-term field experiment which carried on Hailun Agricultural Ecology Station of Chinese Academy of Sciences. Experimental treatments included without fertilizer application ( CK), applying chemical nitrogen and phosphorus fertilizer (NP), and applying N and P fertilizer and organic manure ( NPM). Phosphorus fractions transformation during biological depletion was studied by Hedley' s P fractionation method. [ Result] Compared with no fertilizer application, applying chemical fertilizer and chemical fertilizer with organic manure could increase contents of different forms of phosphorus. The biological depletion pot experiment showed that plant biomass in NPM was 31.72% higher than NP and 54.65% higher than CK. The amounts of plant P uptake in NPM were 1.7 and 2. 1 times higher than those of NP and CK soils, respectively. The concentrations of resin-P in NPM only decreased 0. 85% , which was much lower than that of CK and NP after two successive growing seasons. [Conclusion] Long-term application of chemical fertilizer with organic manure can maintain a high level of reactive P content, improve soil Phosphorus supply capacity and productivity in the agroecosystem.%[目的]研究长期施肥后黑土供磷能力、磷素形态的变化.[方法]利用采自海伦农田生态系统国家野外科学观测研究站长期定位试验地的无肥(CK)、化肥(NP)、化肥配施有机肥( NPM)3个施肥处理黑土进行生物耗竭盆栽试验,并用Hedley方法对土壤磷素形态进行研究.[结果]与长期不施肥处理相比,施化肥与化肥配施有机肥均能明显增加土壤各形态磷素;与无肥处理土壤相比,化肥有机肥配施处理土壤与化肥处理土壤植株的生物量增幅分别为31.72%和54.65%;植

  13. Estimating the long-term effects of in vitro fertilization in Greece: an analysis based on a lifetime-investment model

    Directory of Open Access Journals (Sweden)

    Fragoulakis V

    2013-06-01

    Full Text Available Vassilis Fragoulakis, Nikolaos ManiadakisNational School of Public Health, Department of Health Services Management, Athens, GreeceObjective: To quantify the economic effects of a child conceived by in vitro fertilization (IVF in terms of net tax revenue from the state's perspective in Greece.Methods: Based on previous international experience, a mathematical model was developed to assess the lifetime productivity of a single individual and his/her lifetime transactions with governmental agencies. The model distinguished among three periods in the economic life cycle of an individual: (1 early life, when the government primarily contributes resources through child tax credits, health care, and educational expenses; (2 employment, when individuals begin returning resources through taxes; and (3 retirement, when the government expends additional resources on pensions and health care. The cost of a live birth with IVF was based on the modification of a previously published model developed by the authors. All outcomes were discounted at a 3% discount rate. The data inputs – namely, the economic or demographic variables – were derived from the National Statistical Secretariat of Greece and other relevant sources. To deal with uncertainty, bias-corrected uncertainty intervals (UIs were calculated based on 5000 Monte Carlo simulations. In addition, to examine the robustness of our results, other one-way sensitivity analyses were also employed.Results: The cost of IVF per birth was estimated at €17,015 (95% UI: €13,932–€20,200. The average projected income generated by an individual throughout his/her productive life was €258,070 (95% UI: €185,376–€339,831. In addition, his/her life tax contribution was estimated at €133,947 (95% UI: €100,126–€177,375, while the discounted governmental expenses for elderly and underage individuals were €67,624 (95% UI: €55,211–€83,930. Hence, the net present value of IVF was €60

  14. Nitrogen budget in agroecosystems on gray forest soils under long-term fertilization

    Science.gov (United States)

    Nikitishen, V. I.; Lichko, V. I.

    2008-04-01

    Long-term stationary field experiments were performed to study the efficiency of increased rates of nitrogen fertilizer in crop rotations with cereal crops, perennial grasses, clover, and plow fallow on gray forest soils. It was found that an excess of mineral nitrogen (mainly of nitrates) accumulated in the soil in the case of unbalanced nitrogen fertilization and long-term fallowing creates conditions for the development of unfavorable processes in the nitrogen cycle. Significantly increasing nitrogen losses from the agroecosystem because of leaching and denitrification constitute a depletion hazard for the soil nitrogen pool.

  15. Soil Organic Carbon, Black Carbon, and Enzyme Activity Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    SHAO Xing-hua; ZHENG Jian-wei

    2014-01-01

    The present study aims to understand the effects of long-term fertilization on soil organic carbon (SOC), black carbon (BC), enzyme activity, and the relationships among these parameters. Paddy ifeld was continuously fertilized over 30 yr with nine different fertilizer treatments including N, P, K, NP, NK, NPK, 2NPK (two-fold NPK), NPK+manure (NPKM), and CK (no fertilization), N, 90 kg urea-N ha-1 yr-1; P, 45 kg triple superphosphate-P2O5 ha-1 yr-1; K, 75 kg potassium chloride-K2O ha-1 yr-1;and pig manure, 22 500 kg ha-1 yr-1. Soil samples were collected and determined for SOC, BC content, and enzyme activity. The results showed that the SOC in the NPKM treatment was signiifcantly higher than those in the K, P, and CK treatments. The lowest SOC content was found in the CK treatment. SOC content was similar in the N, NP, NK, NPK, 2NPK, and NPKM treatments. There was no signiifcant difference in BC content among different treatments. The BC-to-SOC ratios (BC/SOC) ranged from 0.50 to 0.63, suggesting that BC might originate from the same source. Regarding enzyme activity, NPK treatment had higher urease activity than NPKM treatment. The urease activity of NPKM treatment was signiifcantly higher than that of 2NPK, NP, N, P, K, CK, and NPKM treatment which produced higher activities of acid phosphatase, catalase, and invertase than all other treatments. Our results indicated that long-term fertilization did not signiifcantly affect BC content. Concurrent application of manure and mineral fertilizers increased SOC content and signiifcantly enhanced soil enzyme activities. Correlation analysis showed that catalase activity was signiifcantly associated with invertase activity, but SOC, BC, and enzyme activity levels were not signiifcantly correlated with one another. No signiifcant correlations were observed between BC and soil enzymes. It is unknown whether soil enzymes play a role in the decomposition of BC.

  16. Profiling of soil volatile organic compounds after long-term application of inorganic, organic and organic-inorganic mixed fertilizers and their effect on plant growth.

    Science.gov (United States)

    Raza, Waseem; Mei, Xinlan; Wei, Zhong; Ling, Ning; Yuan, Jun; Wang, Jichen; Huang, Qiwei; Shen, Qirong

    2017-12-31

    The complexity of soil processes involved in the production, consumption and accumulation of volatile organic compounds (VOCs) makes hard to access the overall dynamics of VOCs in the soil. In this study, the field soil, applied with inorganic (CF), organic (OF) and inorganic-organic mixed (CFOF) fertilizers for ten years was evaluated for the emission of VOCs at different temperature and moisture levels. We identified 30-50 soil emitted VOCs representing the most common soil VOCs groups by using the solid-phase microextraction (SPME) fiber and gas chromatography-mass spectroscopy. The highest total emission of VOCs was found in OF treatment, but it was non-significantly different with CF treatment. The emission of VOCs was significantly increased with the decrease in moisture contents and increase in the temperature of the soil. Among different fertilizer treatments, the emission of VOCs was significantly higher in OF treatment at 5% moisture, and in CF and OF treatments at 35°C. Further, the VOCs emitted from soil treated with CFOF showed the highest increase in plant growth while CF and OF treatments showed similar results. The VOCs were also extracted from the soil using methanol to better understand the dynamics of VOCs. The abundance of VOCs extracted from the soil was 44-61%, while the richness was 65-70% higher than the VOCs emitted from the soil in different treatments. Taken together the results of emitted and extracted VOCs from the soil, we conclude that the fertilizers are able to discriminate among the VOC patterns of soil. In addition, most of the VOCs are retained in the soil and the emission of VOCs from soil depends on the type of VOCs, soil properties and environmental conditions; however, more research is required to find out better soil VOCs analysis methods. Copyright © 2017. Published by Elsevier B.V.

  17. Effect of Long-Term Different Fertilization on Maize Yield Stability in the Northeast Black Soil Region%长期不同施肥对东北黑土区玉米产量稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    高洪军; 彭畅; 张秀芝; 李强; 朱平

    2015-01-01

    [Objective]This research was conducted to reveal the stability difference and dynamic of maize yield in the Northeast Black Soil region of China, and to provide scientific references for establishing the optimal fertilization pattern and promoting the sustainable production of maize.[Method]Based on the long-term experiment on Black Soil fertility and fertilizer efficiency in Gongzhuling city of Jilin province, the respond of maize yield and soil nutrient to eight fertilization patterns were analyzed: non-fertilization (CK), application of single chemical NP (NP), application of single chemical NK (NK), application of single chemical PK (PK), application of single chemical NPK (NPK), mixed application of low amounts of chemical fertilizer and manure (M1NPK), chemical fertilizer plus maize straw (SNPK), and mixed application of high amount chemical fertilizer and manure M2NPK).[Result]It was discovered that maize yield in chemical fertilizer plus organic manure treatments showed a significant increasing trend. There were no significant differences in average yields among the M1NPK, SNPK, and NPK treatments, in which the same N amounts were applied. The NPK treatment had a higher maize yield than the M1NPKand SNPK treatments in the first eleven years, but the result was the opposite in the recent fourteen years. Maize average yields of chemical fertilizer treatments showed an order of NPK>NP>NK>PK and CK during a 25 year period. The yield effects of chemical fertilizers N, P, and K were 33.0, 16.2, and 5.3 kg·kg-1 respectively. The application of organic fertilizer and chemical fertilizer had a higher sustainable yield index (SYI) from 0.712 to 0.798, but theSYI was very low in imbalance fertilization and no fertilizer treatments. The coefficient variation (CV) of maize yield was greater in the CK, PK, or NK treatments, which ranged from 18.5% to 34.7%, while the organic and inorganic fertilizer treatments had a lower CV of between 10.8%-13.0%. The average

  18. Influences of Long-Term Fertilizer and Tillage Management on Soil Fertility of the North China Plain

    Institute of Scientific and Technical Information of China (English)

    NIU Ling-An; HAO Jin-Min; ZHANG Bao-Zhong; NIU Xin-Sheng

    2011-01-01

    In the North China Plain,fertilizer management and tillage practices have been changing rapidly during the last three decades; however,the influences of long-term fertilizer applications and tillage systems on fertility of salt-affected soils have not been well understood under a winter wheat (Triticum aestivum L.)-maize (Zea mays L.) annual double cropping system.A field experiment was established in 1985 on a Cambosol at the Quzhou Experimental Station,China Agricultural University,to investigate the responses of soil fertility to fertilizer and tillage practices.The experiment was established as an orthogonal design with nine treatments of different tillage methods and/or fertilizer applications.In October 2001,composite soil samples were collected from the 0-20 and 20-40 cm layers and analyzed for soil fertility indices.The results showed that after 17 years of nitrogen (N) and phosphorous (P) fertilizer and straw applications,soil organic matter (SOM) in the top layer was increased significantly from 7.00 to 9.30-13.14 g kg-1 in the 0-20 cm layer and from 4.00 to 5.48-7.75 g kg-1 in the 20-40 cm layer.Soil total N (TN) was increased significantly from 0.37 and 0.22 to 0.79-1.11 and 0.61-0.73 g N kg-1 in the 0-20 and 20-40 cm layers,respectively,with N fertilizer application; however,there was no apparent effect of straw application on TN content.The amounts of soil total P (TP) and rapidly available P (RP) were increased significantly from 0.60 to 0.67-1.31 g kg-1 in the 0-20 cm layer and from 0.52 to 0.60-0.73 g kg-1 in the 20-40 cm layer with P fertilizer application,but were decreased with combined N and P fertilizer applications.The applications of N and P fertilizers significantly increased the crop yields,but decreased the rapidly available potassium (RK) in the soil.Straw return could only meet part of the crop potassium requirements.Our results also suggested that though some soil fertility parameters were maintained or enhanced under the long-term

  19. 长期施肥对水稻光合特性及水分利用效率的影响%Effects of long-term fertilization on rice photosynthetic traits and water use efficiency

    Institute of Scientific and Technical Information of China (English)

    袁颖红; 樊后保; 黄欠如; 廖迎春; 黄荣珍

    2009-01-01

    A field experiment has being conducted for 27 years in Jinxian County, Institute of Red Soil in Jiangxi Province (116°20'24" E, 28°15'30" N) to study the effects of fertilization on the rice photosynthetic traits and water use efficiency. Four treatments were installed,i. e., no fertilization (CK), chemical fertilization (N, NP, NPK), organic fertilization (M), and chemi-cal and organic fertilization (NPKM). Long-term fertilization, especially treatment NPKM, in- creased the flag leaf chlorophyll content, net photosynthetic rate, stomatal conductance, transpi-ration rate, and water use efficiency of rice at its all growth stages and the rice yield, and de-creased the flag leaf intercellular CO_2 concentration. With the growth of rice, the chlorophyll content, net photosynthetic rate, stomatal conductance, and transpiration rate decreased, but the intercellular CO_2 concentration increased. The water use efficiency was the greatest at full-head-ing stage. There were significant positive correlations between the chlorophyll content and net photosynthetic rate at various growth stages and the rice yield, Long-term fertilization, especially the combined chemical and organic fertilization, was favorable to the rice growth and develop-ment, water use efficiency, and yield production in red soil region.%在实施了27年的长期田间定位试验区,研究了长期不同施肥对红壤区水稻光合特性及水分利用效率的影响.结果表明:在不施肥(CK)、无机肥(N、NP、NPK)、有机肥(猪粪+紫云英绿肥,M)和无机肥与有机肥配施(NPKM)处理中,长期施用肥料,特别是有机肥与无机肥配施提高水稻各生育期剑叶叶绿素含量、净光合作用速率、气孔导度、蒸腾速率、水分利用效率和水稻产量,降低水稻剑叶胞间CO_2浓度;水稻剑叶叶绿素含量、净光合作用速率、气孔导度、蒸腾速率随发育阶段演进而减小,孕穗期>齐穗期>乳熟期,而胞间CO_2浓度相反;水分利

  20. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    DEFF Research Database (Denmark)

    Zheng, Bang-Xiao; Hao, Xiuli; Ding, Kai

    2017-01-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities...... based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related...... to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance...

  1. Effects of Long-term Different Fertilization on Inorganic Phosphorus Forms in Cinnamon Soil%长期施用不同肥料对栗褐土无机磷组分的影响

    Institute of Scientific and Technical Information of China (English)

    杨艳菊; 王改兰; 王振宙; 聂冰; 熊静; 黄学芳

    2011-01-01

    The effects of long-term fertilization on inorganic phosphorus fractions in lime concretion cinnamon soil were studied using the fraction classification developed by Gu Yi-chu and Jiang Bo-fan. The results show that Long-term application of chemical phosphorus and manure fertilizer may increase the inorganic phosphorus. The main of inorganic phosphorus in cinnamon soil is Ca-P which takes up 80. 0% ,in the next place are O-P,Fe-P and Al-P. Under the Long-term application of chemical phosphorus and manure fertilizer, the components pool of inor ganic phosphorus have increased compared with non-fertilization, except of nitrogen fertilization. In inorganic phos phorus,the related coefficient between Ca2-P, Ca8-P, Calo-P, Al-P, Fe-P and Olsen-P are 0.976 7,0. 886 5, 0.915 5,0.860 2,0.848 4,which reach significant positive relationship,except O-P. Ca2-P,Al-P,Fe-P and Ca10-P are the main sources of Olsen-P can be found by path analysis.%采用顾益初、蒋柏藩的无机磷分级方法,研究了长期施肥条件下栗褐土无机磷组分含量变化及其与土壤有效磷的关系.结果表明:长期施用磷肥和有机肥均能促进栗褐土中无机磷的积累,有机肥与磷肥配施效果更加明显.Ca-P是栗褐土无机磷的主体,占无机磷总量的80.0%,其次是O-P、Fe-P和A1-P.长期施肥处理的无机磷各组分含量与不施肥处理相比均有所增加,而单施氮肥处理无机磷各组分略有下降.无机磷中Ca2-P、Ca8-P、Ca10-P、A1-P、Fe-P与Olsen-P相关系数分别为0.976 7,0.886 5,0.915 5,0.860 2,0.848 4,均达极显著水平,O-P与Olsen-P的相关性不显著.通径分析表明Ca2-P、Al-P、Fe-P、Ca10-P为Olsen-P的主要磷源.

  2. Response of soil nematode communities to long-term application of inorganic fertilizers in the black soil of Northeast China

    Institute of Scientific and Technical Information of China (English)

    Xiaoke ZHANG; Yong JIANG; Lei LIANG; Xiaofan ZHAO; Qi LI

    2009-01-01

    The effects of inorganic fertilizers on soil nematode communities were studied in a long-term fertilization experimental field in the Black Soil Region of Northeast China,where no fertilizer (CK),N fertilizer (N),combined application of N and P (NP),combined application of N and K (NK),and combined application of N,P and K (NPK) were compared.The results showed that the total nematode abundance was not affected significantly by inorganic fertilizers in the long-term field experiment.The numbers of bacterivores increased significantly in the NP treatment compared to the CK treatment,and those of fungivores and plant-parasites were inhibited in the NPK treatment.The similarity between CK and NPK treatment and the nematode diversity were higher than in other treatments.The stability of the soil ecosystem was disturbed by the inorganic fertilizers,as indicated by the change in MI values under different treatments.The response of soil nematodes mainly depended on the types of inorganic fertilizers applied.

  3. Long-term effects of a preoperative smoking cessation programme

    DEFF Research Database (Denmark)

    Villebro, Nete Munk; Pedersen, Tom; Møller, Ann M;

    2008-01-01

    Preoperative smoking intervention programmes reduce post-operative complications in smokers. Little is known about the long-term effect upon smoking cessation.......Preoperative smoking intervention programmes reduce post-operative complications in smokers. Little is known about the long-term effect upon smoking cessation....

  4. Physiological responses to fertilization recorded in tree rings: isotopic lessons from a long-term fertilization trial - 2008

    Science.gov (United States)

    Nitrogen fertilizer applications are common land-use management tools, but details on physiological responses to these applications are often lacking, particularly for long-term responses over decades of forest management. We used tree-ring growth patterns and stable isotopes to...

  5. Physiological responses to fertilization recorded in tree rings: Isotopic lessons from a long-term fertilization trial

    Science.gov (United States)

    Nitrogen fertilizer applications are common land use management tools, but details on physiological responses to these applications are often lacking, particularly for long-term responses over decades of forest management. We used tree ring growth patterns and stable isotopes to ...

  6. The Effect of Modality on Long-Term Recognition Memory.

    Science.gov (United States)

    Dean, Raymond S.; And Others

    1988-01-01

    The effects of visual and auditory modes of input on long-term memory were examined in two experiments, each with 40 and 80 undergraduates, respectively. In both experiments, visual stimulus attributes were a more salient dimension than were auditory features in the long-term encoding and retrieval process. (SLD)

  7. Effects of Long-termed In-situ Fertilization on Wheat Rhizosphere Soil Nutrition in Chao Soil%潮土长期定位施肥对小麦根际土壤营养的影响

    Institute of Scientific and Technical Information of China (English)

    介晓磊; 杨先明; 刘世亮; 刘芳; 化党领; 李学军; 李宗军

    2011-01-01

    在长期定位施肥的基础上,采用盆栽试验,研究了不同施肥处理对冬小麦根际土壤与非根际土壤中pH、有机质含量及速效养分含量差异的影响.结果表明,(1)CK和PK处理在不同生育期其根际pH值均低于根外,土壤有机质含量逐渐下降.氮肥及和P、K配施的处理中,根际和非根际的pH值均低于PK和CK.N、NP、NPK处理的根际土壤有机质从拔节到成熟期有先下降后上升的趋势,而NK处理根际和非根际土壤有机质含量均逐渐下降.有机肥和化肥配施的处理中,在拔节期根际pH值均小于根外,在抽穗期和成熟期却相反,有机质含量从拔节期到成熟期均高于化肥处理.(2)CK和PK处理,土壤速效氮在各个时期均较其它处理低.长期施用氮肥和其它肥料配施(N、NP、NK、NPK)处理,在拔节期时,根际与非根际土壤的速效氮含量差异不明显,而根际的速效磷含量最高;到成熟期时,以N、NK处理的速效氮含量最高;偏施钾肥(NK和PK)处理的根际与非根际土壤速效钾含量变化不明显,但高于NPK处理;长期施用有机肥和NPK处理根际土速效氮含量较化肥处理高,以MNPK和1.5MNPK处理表现最明显.除SNPK外,各处理根际和非根际土速效磷含量均明显高于化肥处理,以1.5MNPK处理含量最高.%Based on a 15-year long-term fertilization experiment in Chao soil, the effects of different fertilization treatments on pH value, organic matter and available nutrition content in wheat rhizosphere soil and non-rhizosphere soil were studied by pot experiment. The results showed that: (1) The pH values of the CK and PK treatments were much lower in the rhizosphere soil than that in the bulk soil, and soil organic matter content was gradually declining. The pH values in rhizosphere soil and bulk soil of applied nitrogen fertilizer and combined with P, K treatments were less than those of PK and CK treatments. The soil organic matter contents of N, NP and NPK

  8. [Variation characteristics of soil carbon sequestration under long-term different fertilization in red paddy soil].

    Science.gov (United States)

    Huang, Jing; Zhang, Yang-zhu; Gao, Ju-sheng; Zhang, Wen-ju; Liu, Shu-jun

    2015-11-01

    The objective of this study was to clarify the changes of soil organic carbon (SOC) content, the saturation capacity of soil carbon sequestration and its cooperation with carbon input (crop source and organic fertilizer source carbon) under long-term (1982-2012) different fertilization in red paddy soil. The results showed that fertilization could increase SOC content. The SOC content of all the fertilization treatments demonstrated a trend of stabilization after applying fertilizer for 30 years. The SOC content in the treatments applying organic manure with mineral fertilizers was between 21.02 and 21.24 g · kg(-1), and the increase rate ranged from 0.41 to 0.59 g · kg(-1) · a(-1). The SOC content in the treatments applying mineral fertilizers only was 15.48 g · kg(-1). The average soil carbon sequestration in the treatments that applied organic manure with mineral fertilizers ranged from 43.61 to 48.43 t C · hm(-2), and the average SOC storage over the years in these treatments was significantly greater than those applying mineral fertilizers only. There was an exponentially positive correlation between C sequestration efficiency and annual average organic C input. It must input exogenous organic carbon at least at 0. 12 t C · hm(-2) · a(-1) to maintain the balance of soil organic carbon under the experimental conditions.

  9. Effects of enhancing soil organic carbon sequestration in the topsoil by fertilization on crop productivity and stability: Evidence from long-term experiments with wheat-maize cropping systems in China.

    Science.gov (United States)

    Zhang, Xubo; Sun, Nan; Wu, Lianhai; Xu, Minggang; Bingham, Ian J; Li, Zhongfang

    2016-08-15

    Although organic carbon sequestration in agricultural soils has been recommended as a 'win-win strategy' for mitigating climate change and ensuring food security, great uncertainty still remains in identifying the relationships between soil organic carbon (SOC) sequestration and crop productivity. Using data from 17 long-term experiments in China we determined the effects of fertilization strategies on SOC stocks at 0-20cm depth in the North, North East, North West and South. The impacts of changes in topsoil SOC stocks on the yield and yield stability of winter wheat (Triticum aestivum L.) and maize (Zea mays L.) were determined. Results showed that application of inorganic fertilizers (NPK) plus animal manure over 20-30years significantly increased SOC stocks to 20-cm depth by 32-87% whilst NPK plus wheat/maize straw application increased it by 26-38% compared to controls. The efficiency of SOC sequestration differed between regions with 7.4-13.1% of annual C input into the topsoil being retained as SOC over the study periods. In the northern regions, application of manure had little additional effect on yield compared to NPK over a wide range of topsoil SOC stocks (18->50MgCha(-1)). In the South, average yield from manure applied treatments was 2.5 times greater than that from NPK treatments. Moreover, the yield with NPK plus manure increased until SOC stocks (20-cm depth) increased to ~35MgCha(-1). In the northern regions, yield stability was not increased by application of NPK plus manure compared to NPK, whereas in the South there was a significant improvement. We conclude that manure application and straw incorporation could potentially lead to SOC sequestration in topsoil in China, but beneficial effects of this increase in SOC stocks to 20-cm depth on crop yield and yield stability may only be achieved in the South.

  10. Changes in cropland topsoil organic carbon with different fertilizations under long-term agro-ecosystem experiments across mainland China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of mainland China.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China’s croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.

  11. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Directory of Open Access Journals (Sweden)

    Dan Lawrence

    Full Text Available Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  12. Grain yield and crop N offtake in response to residual fertilizer N in long-term field experiments

    DEFF Research Database (Denmark)

    Petersen, Jens; Thomsen, Ingrid Kaag; Mattsson, L.

    2010-01-01

    Organic inputs [e.g. animal manure (AM) and plant residues] contribute directly to the soil organic N pool, whereas mineral N fertilizer contributes indirectly by increasing the return of the crop residues and by microbial immobilization. To evaluate the residual effect of N treatments established...... in four long-term (>35 yr) field experiments, we measured the response of barley (grain yield and N offtake at crop maturity) to six rates (0, 30, 60, 90, 120 and 150 kg N/ha) of mineral fertilizer N (Nnew) applied in subplots replacing the customary long-term plot treatments of fertilizer inputs (Nprev......). Rates of Nprev above 50-100 kg N/ha had no consistent effect on the soil N content, but this was up to 20% greater than that in unfertilized treatments. Long-term unfertilized plots should not be used as control to test the residual value of N in modern agriculture with large production potentials...

  13. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    Science.gov (United States)

    Zheng, Bang-Xiao; Hao, Xiu-Li; Ding, Kai; Zhou, Guo-Wei; Chen, Qing-Lin; Zhang, Jia-Bao; Zhu, Yong-Guan

    2017-01-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance of pqqC gene (pqqC/16S). The decreased iPSB abundance was strongly related to pH decline and total N increase, revealing that the long-term N additions may cause pH decline and subsequent P releases relatively decreasing the demands of the iPSB community. The methodology and understanding obtained here provides insights into the ecology of inorganic P solubilizers and how to manipulate for better P use efficiency. PMID:28181569

  14. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    Science.gov (United States)

    Zheng, Bang-Xiao; Hao, Xiu-Li; Ding, Kai; Zhou, Guo-Wei; Chen, Qing-Lin; Zhang, Jia-Bao; Zhu, Yong-Guan

    2017-02-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance of pqqC gene (pqqC/16S). The decreased iPSB abundance was strongly related to pH decline and total N increase, revealing that the long-term N additions may cause pH decline and subsequent P releases relatively decreasing the demands of the iPSB community. The methodology and understanding obtained here provides insights into the ecology of inorganic P solubilizers and how to manipulate for better P use efficiency.

  15. Biogeochemistry: Long-term effects of permafrost thaw

    Science.gov (United States)

    Zona, Donatella

    2016-09-01

    Carbon emissions from the Arctic tundra could increase drastically as global warming thaws permafrost. Clues now obtained about the long-term effects of such thawing on carbon dioxide emissions highlight the need for more data.

  16. Differential responses of ammonia-oxidizing archaea and bacteria to long-term fertilization in a New England salt marsh

    Directory of Open Access Journals (Sweden)

    Xuefeng ePeng

    2013-01-01

    Full Text Available Since the discovery of ammonia-oxidizing archaea (AOA, new questions have arisen about population and community dynamics and potential interactions between AOA and ammonia-oxidizing Bacteria (AOB. We investigated the effects of long-term fertilization on AOA and AOB in the Great Sippewissett Marsh, Falmouth, MA, USA to address some of these questions. Sediment samples were collected from low and high marsh habitats in July 2009 from replicate plots that received low (LF, high (HF, and extra high (XF levels of a mixed NPK fertilizer biweekly during the growing season since 1974. Additional untreated plots were included as controls (C. Terminal restriction fragment length polymorphism analysis of the amoA genes revealed distinct shifts in AOB communities related to fertilization treatment, but the response patterns of AOA were less consistent. Four AOB operational taxonomic units (OTUs predictably and significantly responded to fertilization, but only one AOA OTU showed a significant pattern. Betaproteobacterial amoA gene sequences within the Nitrosospira-like cluster dominated at C and LF sites, while sequences related to Nitrosomonas spp. dominated at HF and XF sites. We identified some clusters of AOA sequences recovered primarily from high fertilization regimes, but other clusters consisted of sequences recovered from all fertilization treatments, suggesting greater physiological diversity. Surprisingly, fertilization appeared to have little impact on abundance of AOA or AOB. In summary, our data reveal striking patterns for AOA and AOB in response to long-term fertilization, and also suggest a missing link between community composition and abundance and nitrogen processing in the marsh.

  17. Differential responses of ammonia-oxidizing archaea and bacteria to long-term fertilization in a New England salt marsh.

    Science.gov (United States)

    Peng, Xuefeng; Yando, Erik; Hildebrand, Erica; Dwyer, Courtney; Kearney, Anne; Waciega, Alex; Valiela, Ivan; Bernhard, Anne E

    2012-01-01

    Since the discovery of ammonia-oxidizing archaea (AOA), new questions have arisen about population and community dynamics and potential interactions between AOA and ammonia-oxidizing bacteria (AOB). We investigated the effects of long-term fertilization on AOA and AOB in the Great Sippewissett Marsh, Falmouth, MA, USA to address some of these questions. Sediment samples were collected from low and high marsh habitats in July 2009 from replicate plots that received low (LF), high (HF), and extra high (XF) levels of a mixed NPK fertilizer biweekly during the growing season since 1974. Additional untreated plots were included as controls (C). Terminal restriction fragment length polymorphism analysis of the amoA genes revealed distinct shifts in AOB communities related to fertilization treatment, but the response patterns of AOA were less consistent. Four AOB operational taxonomic units (OTUs) predictably and significantly responded to fertilization, but only one AOA OTU showed a significant pattern. Betaproteobacterial amoA gene sequences within the Nitrosospira-like cluster dominated at C and LF sites, while sequences related to Nitrosomonas spp. dominated at HF and XF sites. We identified some clusters of AOA sequences recovered primarily from high fertilization regimes, but other clusters consisted of sequences recovered from all fertilization treatments, suggesting greater physiological diversity. Surprisingly, fertilization appeared to have little impact on abundance of AOA or AOB. In summary, our data reveal striking patterns for AOA and AOB in response to long-term fertilization, and also suggest a missing link between community composition and abundance and nitrogen processing in the marsh.

  18. 长期不同施肥处理对栗褐土可培养微生物数量的影响%Effects of long-term different fertilization on culturable microorganisms quantity in cinnamon soil

    Institute of Scientific and Technical Information of China (English)

    杨艳菊; 王改兰; 张海鹏; 赵旭; 熊静; 黄学芳

    2013-01-01

    The effects of long-term fertilization on soil microorganism populations and their quantity and the correlation between microorganism and available nutrients basis in cinnamon soil were studied in this paper.The results showed that bacterial was the main microorganism in cinnamon soil with the proportion of 92.72% ~95.91%.Organic fertilizer could significantly increase the quantity of soil microorganism for bacteria quantity of M1 N,actinomycetes quantity of M1 NP,fungi quantity of M2NP were the highest of all treatments and the bacteria quantity difference of M1N compared with the control was significant.The quantity of phosphate-solubilizing bacteria also could be significantly increased under the conditions of using organic fertilizer.The correlations between bacteria,fungi,actinomycetes and inorganic phosphate-solubilizing bacteria with available nitrogen,available phosphorus and available potassium were in significant level.%在24年长期定位试验的基础上,以选择性培养基为基础研究长期定位施肥对土壤微生物种群及数量的影响,同时测定了土壤速效养分的含量,探讨了微生物与土壤速效养分的相关关系.结果表明,栗褐土微生物以细菌为主体,约占微生物总数的92.72% ~95.91%;施用有机肥可以显著提高土壤微生物的数量,处理M1N细菌数量最多,显著高于对照;处理M1NP放线菌数量最多,处理M2NP真菌数量最多;施用有机肥可以显著提高土壤解磷细菌数量;细菌、真菌、放线菌和无机磷细菌与碱解氮、速效磷和速效钾相关性均达显著或极显著水平.

  19. Long-term memory, sleep, and the spacing effect.

    Science.gov (United States)

    Bell, Matthew C; Kawadri, Nader; Simone, Patricia M; Wiseheart, Melody

    2014-01-01

    Many studies have shown that memory is enhanced when study sessions are spaced apart rather than massed. This spacing effect has been shown to have a lasting benefit to long-term memory when the study phase session follows the encoding session by 24 hours. Using a spacing paradigm we examined the impact of sleep and spacing gaps on long-term declarative memory for Swahili-English word pairs by including four spacing delay gaps (massed, 12 hours same-day, 12 hours overnight, and 24 hours). Results showed that a 12-hour spacing gap that includes sleep promotes long-term memory retention similar to the 24-hour gap. The findings support the importance of sleep to the long-term benefit of the spacing effect.

  20. Wheat Grain Yield and Yield Stability in a Long-Term Fertilization Experiment on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    HAO Ming-De; FAN Jun; WANG Quan-Jiu; DANG Ting-Hui; GUO Sheng-Li; WANG Ji-Jun

    2007-01-01

    To provide a scientific basis for sustainable land management,a 20-year fertility experiment Was conducted in Changwu County,Shaanxi Province,China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis.The experiment consisted of 17fertilizer treatments.containing the combinations of different N and P levels,with three replications arranged in a randomized complete block design.Nitrogen fertilizer was applied as urea,and P was applied as calcium superphosphate.Fertilizer rates had a large effect on the response of wheat yield to fertilization.Phosphorus,combined with N,increased yield significantly(P≤0.01).In the unfertilized control and the N or P sole application treatments,wheat yield had a declining trend although it was not statistically significant.Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.

  1. Effect of Long-Term Fertilization on Pb, As Contents of Soil and Maize Grain%长期施肥对土壤及玉米籽粒中Pb、As含量的影响

    Institute of Scientific and Technical Information of China (English)

    杨振兴; 周怀平; 解文艳; 关春林; 车丽

    2015-01-01

    Objective] The objective of this study is to explore the dynamic changes on contents of heavy metal Pb, As in cinnamon soil of long-term fertilization.[Method]Based on the experiment on 22-year application of nitrogen, phosphorus and organic fertilizers and the analysis of Pb and As contents in 0-20 and 20-40 cm soil layers and maize grains in 2013, the effects of accumulation state, interannual variation characteristics and profile distribution on changes of Pb and As contents in cinnamon soil and maize grains after long-term fertilization were studied.[Result]The soil Pb and As contents of no fertilizer treatment decreased, others increased. The soil Pb content increased 1.77-8.41 mg·kg-1and variation of Pb was between 4.42% and 20.95%, respectively, as compared to the baseline levels. The soil As content decreased 17.10%-41.54%, respectively, as compared to the baseline levels. The content of Pb has obvious properties of surface-accumulation. The content of As in 20-40 cm soil layer was more than that in the plough layer. The contents of two heavy metals in soil tested in 2013 did not exceed the upper limits of the grade II criteria of the Environment Quality Standard for Soil. Pb and As contents in cinnamon soil were not significantly affected by the use of phosphate and organic fertilizers among treatments. Pb and As contents in maize grains analyzed in 2013 were below their respective thresholds of the national food safety standard.[Conclusion]The accumulation of heavy metal Pb in fertilization treatments was demonstrated. So, more attention should be paid to control the amount of fertilizer application.%【目的】探究褐土区长期施肥农田土壤重金属Pb、As含量的动态变化规律。【方法】基于22年的氮磷化肥与有机肥配施长期定位试验,通过对0—20及20—40 cm土层及2013年玉米籽粒Pb、As含量的测定,分析褐土农田Pb、As的累积状况、年际变化特征、剖面分布特征及对玉米籽粒Pb

  2. Long-term fertilization of a boreal Norway spruce forest increases the temperature sensitivity of soil organic carbon mineralization.

    Science.gov (United States)

    Coucheney, Elsa; Strömgren, Monika; Lerch, Thomas Z; Herrmann, Anke M

    2013-12-01

    Boreal ecosystems store one-third of global soil organic carbon (SOC) and are particularly sensitive to climate warming and higher nutrient inputs. Thus, a better description of how forest managements such as nutrient fertilization impact soil carbon (C) and its temperature sensitivity is needed to better predict feedbacks between C cycling and climate. The temperature sensitivity of in situ soil C respiration was investigated in a boreal forest, which has received long-term nutrient fertilization (22 years), and compared with the temperature sensitivity of C mineralization measured in the laboratory. We found that the fertilization treatment increased both the response of soil in situ CO2 effluxes to a warming treatment and the temperature sensitivity of C mineralization measured in the laboratory (Q10). These results suggested that soil C may be more sensitive to an increase in temperature in long-term fertilized in comparison with nutrient poor boreal ecosystems. Furthermore, the fertilization treatment modified the SOC content and the microbial community composition, but we found no direct relationship between either SOC or microbial changes and the temperature sensitivity of C mineralization. However, the relation between the soil C:N ratio and the fungal/bacterial ratio was changed in the combined warmed and fertilized treatment compared with the other treatments, which suggest that strong interaction mechanisms may occur between nutrient input and warming in boreal soils. Further research is needed to unravel into more details in how far soil organic matter and microbial community composition changes are responsible for the change in the temperature sensitivity of soil C under increasing mineral N inputs. Such research would help to take into account the effect of fertilization managements on soil C storage in C cycling numerical models.

  3. [Degradation dynamics of POPs atrazine in soils under long-term located fertilization conditions].

    Science.gov (United States)

    Wang, Jun; Zhu, Lu-sheng; Xie, Hui; Song, Yan; Sun, Rui-lian; Zhang, Fu-dao

    2007-12-01

    To evaluate the difference of POPs atrazine degradation dynamics in soils under different fertilization conditions, we set up an analysis method of the atrazine residue in soils and studied residue dynamics of atrazine in soils under a long-term located fertilization conditions. After extracted by surging with acetone, liquid-liquid partition and eluted through florisil, the residue of atrazine in soils was detected by gas chromatogram with 63Ni-ECD. The minimum detectable quantity of atrazine is 6.4 x 10(-12) g and the minimum detectable concentration is 6.4 x 10(-9) g x kg(-1) in the soil. The spiked recoveries of atrazine with the three concentration of 0.11, 1.1, 11.0 mg x kg(-1) in soils are 91.41% +/- 4.36%, 93.58% +/- 4.54%, 90.35% +/- 3.59%, according with the request of pesticide residue analysis. The degradation of atrazine in soil under a long-term located fertilization conditions was studied. The results show the degradation of atrazine follows stair dynamic equation, and the degradation half-life of atrazine in soils fertilized with CK, NPK, NPK + M, NPK + S are 20.6, 23.0, 28.5, 33.2 d, respectively. Subjected to analysis of LSR, NPK and organic fertilizers are obviously propitious to the degradation of atrazine. The separate regression and stepwise regression analysis prove the degradation half-life of atrazine in soils is well related with the content of alkaline nitrogen, organic matter and total nitrogen, and the coefficients are 0.9983, 0.9826 and 0.9521, respectively. Maybe the reason is that these soil nutrient substance offers enough the element carbon and nitrogen for action of microbe, and the higher action of microbe quickens the degradation of atrazine in soils.

  4. Fertility treatment: long-term growth and mental development of the children.

    Science.gov (United States)

    Bay, Bjørn

    2014-10-01

    Fertility treatment has been associated with obstetrical and perinatal complications. It is, however, uncertain whether fertility treatment or parental subfertility is associated with long-term development of the children. We aimed to assess the growth and mental health of children and adolescents conceived after fertility treatment compared to spontaneously conceived controls. First, we evaluated all previous studies comparing neurodevelopmental outcomes between children conceived after fertility treatment and spontaneous conceived controls. The systematic review clarified methodological limitations in the existing literature on the long-term development of children conceived after medical assisted reproduction. Although several studies had been published, large, well-controlled studies with long-term follow-up and thorough statistical adjustments were still few. Second, we evaluated the children's mental health by assessing the risk of mental disorders. We studied a population of 555,828 children conceived after spontaneous conception and 33,139 children conceived after fertility treatment with follow-up in 2012 when the children were 8-17 years old. The absolute risk and hazard ratio of overall and specific mental disorders were estimated while adjusting for potential confounding variables. Further, we estimated the association between subtypes of procedures, hormonal treatment, gamete types and cause of infertility on the one hand and the risk of mental disorders on the other. Children conceived after ovulation induction had a low, but significantly increased risks of autism spectrum disorders, hyperkinetic disorders, conduct, emotional, or social disorders, and tic disorders. Children conceived after IVF or ICSI showed no increased risk, except for a small risk of tic disorders. There was no risk systematically related to any specific type of hormone drug treatment. Thus, the increased risks may rely on residual confounding such as unknown parental factors

  5. [Dynamics of microbial biomass C in a black soil under long-term fertilization and related affecting factors].

    Science.gov (United States)

    Li, Dongpo; Wu, Zhijie; Chen, Lijun; Zhu, Ping; Ren, Jun; Peng, Chang; Liang, Chenghua

    2004-08-01

    The effect of long-term fertilization on the dynamics of microbial biomass C in a typical black soil of Northeastern China was studied in a field trail treated by different fertilizations. The results showed that the amount of soil microbial biomass C under different fertilizations varied significantly with growth stages. It was the highest in farmyard manure (M2 and M4) treatments, with a less seasonal fluctuation, second in NPK treatment, the peak at sowing period, and the lowest in CK, the peak at wax maturity stage. No significant correlation was found between the dynamic changes of soil microbial biomass C and soil biological, physical and chemical properties in all treatments, but the correlation of soil microbial biomass C with the contents of N, P and K in plants and that of crude protein in grain was significantly positive.

  6. Basic Soil Productivity of Spring Maize in Black Soil Under Long-Term Fertilization Based on DSSAT Model

    Institute of Scientific and Technical Information of China (English)

    ZHA Yan; WU Xue-ping; HE Xin-hua; ZHANG Hui-min; GONG Fu-fei; CAI Dian-xiong; ZHU Ping; GAO Hong-jun

    2014-01-01

    Increasing basic farmland soil productivity has signiifcance in reducing fertilizer application and maintaining high yield of crops. In this study, we deifned that the basic soil productivity (BSP) is the production capacity of a farmland soil with its own physical and chemical properties for a speciifc crop season under local environment and ifeld management. Based on 22-yr (1990-2011) long-term experimental data on black soil (Typic hapludoll) in Gongzhuling, Jilin Province, Northeast China, the decision support system for an agro-technology transfer (DSSAT)-CERES-Maize model was applied to simulate the yield by BSP of spring maize (Zea mays L.) to examine the effects of long-term fertilization on changes of BSP and explore the mechanisms of BSP increasing. Five treatments were examined:(1) no-fertilization control (control);(2) chemical nitrogen, phosphorus, and potassium (NPK); (3) NPK plus farmyard manure (NPKM); (4) 1.5 time of NPKM (1.5NPKM) and (5) NPK plus straw (NPKS). Results showed that after 22-yr fertilization, the yield by BSP of spring maize signiifcantly increased 78.0, 101.2, and 69.4% under the NPKM, 1.5NPKM and NPKS, respectively, compared to the initial value (in 1992), but not signiifcant under NPK (26.9%increase) and the control (8.9%decrease). The contribution percentage of BSP showed a signiifcant rising trend (PNPKM>NPK≈NPKS, indicating that organic manure combined with chemical fertilizers (1.5NPKM and NPKM) could more effectively increase BSP compared with the inorganic fertilizer application alone (NPK) in the black soil. This study showed that soil organic matter (SOM) was the key factor among various fertility factors that could affect BSP in the black soil, and total N, total P and/or available P also played important role in BSP increasing. Compared with the chemical fertilization, a balanced chemical plus manure or straw fertilization (NPKM or NPKS) not only increased the concentrations of soil nutrient, but also improved the

  7. Is subfertility or fertility treatment associated with long-term growth in the offspring?

    DEFF Research Database (Denmark)

    Bay, Bjørn; Mortensen, Erik Lykke; Kesmodel, Ulrik Schiøler

    2014-01-01

    OBJECTIVE: To study whether fertility treatment or subfertility is associated with long-term growth in the offspring. DESIGN: A prospective follow-up study including 1,773 singletons participating in the Lifestyle During Pregnancy Study at the age of 5. SETTING: Research centers. PATIENT......(S): A total of 3,478 mother-child pairs were sampled from the Danish National Birth Cohort, and 1,773 completed the outcome measurements. A total of 69 children were born after fertility treatment, whereas 132 were born to subfertile parents conceiving spontaneously but after a time to pregnancy of more than......, perinatal outcomes, and postnatal parental lifestyle characteristics were obtained from the Danish National Birth Cohort, the 5-year follow-up, and Danish health registers. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Adjusted mean differences in body weight, height, body mass index (BMI), and head...

  8. Increased ectomycorrhizal fungal abundance after long-term fertilization and warming of two arctic tundra ecosystems

    DEFF Research Database (Denmark)

    Clemmensen, Karina Engelbrecht; Michelsen, Anders; Jonasson, Sven Evert;

    2006-01-01

    the response in EM fungal abundance to long-term warming and fertilization in two arctic ecosystems with contrasting responses of the EM shrub Betula nana. •  Ergosterol was used as a biomarker for living fungal biomass in roots and organic soil and ingrowth bags were used to estimate EM mycelial production....... We measured 15N and 13C natural abundance to identify the EM-saprotrophic divide in fungal sporocarps and to validate the EM origin of mycelia in the ingrowth bags. •  Fungal biomass in soil and EM mycelial production increased with fertilization at both tundra sites, and with warming at one site....... This was caused partly by increased dominance of EM plants and partly by stimulation of EM mycelial growth. •  We conclude that cycling of carbon and nitrogen through EM fungi will increase when strongly nutrient-limited arctic ecosystems are exposed to a warmer and more nutrient-rich environment. This has...

  9. Soil pH Dynamics and Nitrogen Transformations Under Long-Term Chemical Fertilization in Four Typical Chinese Croplands

    Institute of Scientific and Technical Information of China (English)

    MENG Hong-qi; XU Ming-gang; L Jia-long; HE Xin-hua; LI Jian-wei; SHI Xiao-jun; PENG Chang; WANG Bo-ren; ZHANG Hui-min

    2013-01-01

    Long-term fertilization experiment provides the platform for understanding the proton budgets in nitrogen transformations of agricultural ecosystems. We analyzed the historical (1990-2005) observations on four agricultural long-term experiments in China (Changping, Chongqing, Gongzhuling and Qiyang) under four different fertilizations, i.e., no-fertilizer (control), sole chemical nitrogen fertilizer (FN), sole chemical phosphorous and potassium fertilizers (FPK) and chemical nitrogen, phosphorous and potassium fertilizers (FNPK). The significant decline in topsoil pH was caused not only by chemical N fertilization (0.29 and 0.89∆pH at Gongzhuling and Qiyang, respectively) but also by chemical PK fertilization (0.59∆pH at Gongzhuling). The enhancement of available nutrients in the topsoil due to long-term direct nutrients supply with chemical fertilizers was in the descending order of available P (168-599%)>available K (16-189%)>available N (9-33%). The relative rate of soil pH decline was lower under long-term judicious chemical fertilization (-0.036-0.034 ∆pH yr-1) than that under long-term sole N or PK fertilization (0.016-0.086 ∆pH yr-1). Long-term judicious chemical fertilization with N, P and K elements decreases the nutritional limitation to normal crop growth, under which more N output was distributed in biomass removal rather than the loss via nitrate leaching. We concluded that the N distribution percentage of nitrate leaching to biomass removal might be a suitable indicator to the sensitivity of agricultural ecosystems to acid inputs.

  10. LONG-TERM EFFECT OF HOMOHARRINGTONINE ON CHRONIC GRANULOCYTIC LEUKEMIA

    Institute of Scientific and Technical Information of China (English)

    LI Yu-feng; ZHU Jia-bin; WANG Chun-ling; DING Bang-he; LI Yuan-yuan; XUAN Heng-bao; QIAN Mo-sheng

    2005-01-01

    Objective: To observe the long-term effect of homoharringtonine (HHT) on chronic granulocytic leukemia (CGL) and its pharmacological mechanism. Methods: 76 patients with newly diagnosed early chronic phase CGL received treatment of merely 1.5 mg/m2 daily HHT for induction remission and long-term maintenance treatment. The apoptosis rate of bone marrow CD34+ cells induced by HHT was assayed with flow cytometer. Results: 86.8% patients achieved CHR, 13.2% patients PHR and 31.8% patients got cytogenetic response in HHT treatment group, which was longer than 31 (8-54) months in hydroxyurea (HU) group (P<0.05). The effect of apoptosis induction HHT was stronger on CGL-CP patients bone marrow CD34+ cells than on normal person bone marrow CD34+ cells. Conclusion: HHT is a very effective drug for remission induction and long-term maintenance treatment in early chronic phase CGL patients.

  11. Modelling crop yield, soil organic C and P under variable long-term fertilizer management in China

    Science.gov (United States)

    Zhang, Jie; Xu, Guang; Xu, Minggang; Balkovič, Juraj; Azevedo, Ligia B.; Skalský, Rastislav; Wang, Jinzhou; Yu, Chaoqing

    2016-04-01

    Phosphorus (P) is a major limiting nutrient for plant growth. P, as a nonrenewable resource and the controlling factor of aquatic entrophication, is critical for food security and human future, and concerns sustainable resource use and environmental impacts. It is thus essential to find an integrated and effective approach to optimize phosphorus fertilizer application in the agro-ecosystem while maintaining crop yield and minimizing environmental risk. Crop P models have been used to simulate plant-soil interactions but are rarely validated with scattered long-term fertilizer control field experiments. We employed a process-based model named Environmental Policy Integrated Climate model (EPIC) to simulate grain yield, soil organic carbon (SOC) and soil available P based upon 8 field experiments in China with 11 years dataset, representing the typical Chinese soil types and agro-ecosystems of different regions. 4 treatments, including N, P, and K fertilizer (NPK), no fertilizer (CK), N and K fertilizer (NK) and N, P, K and manure (NPKM) were measured and modelled. A series of sensitivity tests were conducted to analyze the sensitivity of grain yields and soil available P to sequential fertilizer rates in typical humid, normal and drought years. Our results indicated that the EPIC model showed a significant agreement for simulating grain yields with R2=0.72, index of agreement (d)=0.87, modeling efficiency (EF)=0.68, pmanagement practices.

  12. Impact of Long-Term Fertilization on Phosphorus Status in Black Soil

    Institute of Scientific and Technical Information of China (English)

    HAN Xiao-Zeng; SONG Chun-Yu; WANG Shou-Yu; C. TANG

    2005-01-01

    A twelve-year field trial was carried out to determine the impact of long-term fertilization on phosphorus (P) distribution in the soil profile, P balance, and the transformation and availability of soil P in a black soil (Phaeozem, FAO). Under a wheat-soybean-corn rotation, during twelve years where no fertilizer was applied, crops removed 60 and 81 mg P kg-1 soil in the control and NK treatment, respectively. About one third of the P absorbed by crops was originated from organic P. Ca2-P, Ca8-P, Al-P and Fe-P were the main forms of inorganic P absorbed by crops. The surplus P from fertilization remained in the 0-20 cm soil layer and increased with the application rate of P. The combined application of NP or NPK increased available P to a lesser extent than the combined application of PK. Fertilizer P had mainly transformed to the Al-P, Fe-P, Ca2-P, and Ca8-P forms. By using the P budget (X), changes in total P (Y1) and available P (Y2) in soils under the current cropping system could be predicted by the equations: Y1 = 0.02 + 1.01X and Y2 = 2.08 + 0.15X.

  13. Community structure of ammonia-oxidizing bacteria under long-term application of mineral fertilizer and organic manure in a sandy loam soil.

    Science.gov (United States)

    Chu, Haiyan; Fujii, Takeshi; Morimoto, Sho; Lin, Xiangui; Yagi, Kazuyuki; Hu, Junli; Zhang, Jiabao

    2007-01-01

    The effects of mineral fertilizer (NPK) and organic manure on the community structure of soil ammonia-oxidizing bacteria (AOB) was investigated in a long-term (16-year) fertilizer experiment. The experiment included seven treatments: organic manure, half organic manure N plus half fertilizer N, fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK, and the control (without fertilization). N fertilization greatly increased soil nitrification potential, and mineral N fertilizer had a greater impact than organic manure, while N deficiency treatment (PK) had no significant effect. AOB community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) of the amoA gene, which encodes the alpha subunit of ammonia monooxygenase. DGGE profiles showed that the AOB community was more diverse in N-fertilized treatments than in the PK-fertilized treatment or the control, while one dominant band observed in the control could not be detected in any of the fertilized treatments. Phylogenetic analysis showed that the DGGE bands derived from N-fertilized treatments belonged to Nitrosospira cluster 3, indicating that N fertilization resulted in the dominance of Nitrosospira cluster 3 in soil. These results demonstrate that long-term application of N fertilizers could result in increased soil nitrification potential and the AOB community shifts in soil. Our results also showed the different effects of mineral fertilizer N versus organic manure N; the effects of P and K on the soil AOB community; and the importance of balanced fertilization with N, P, and K in promoting nitrification functions in arable soils.

  14. Responses of absolute and specific soil enzyme activities to long term additions of organic and mineral fertilizer.

    Science.gov (United States)

    Zhang, Xinyu; Dong, Wenyi; Dai, Xiaoqin; Schaeffer, Sean; Yang, Fengting; Radosevich, Mark; Xu, Lili; Liu, Xiyu; Sun, Xiaomin

    2015-12-01

    Long-term phosphorus (P) and nitrogen (N) applications may seriously affect soil microbial activity. A long-term field fertilizer application trial was established on reddish paddy soils in the subtropical region of southern China in 1998. We assessed the effects of swine manure and seven different rates or ratios of NPK fertilizer treatments on (1) the absolute and specific enzyme activities per unit of soil organic carbon (SOC) or microbial biomass carbon (MBC) involved in C, N, and P transformations and (2) their relationships with soil environmental factors and soil microbial community structures. The results showed that manure applications led to increases in the absolute and specific activities of soil β-1,4-glucosidase(βG), β-1,4-N-acetylglucosaminidase (NAG), and leucine aminopeptidase (LAP). The absolute and specific acid phosphatase (AP) activities decreased as mineral P fertilizer application rates and ratios increased. Redundancy analysis (RDA) showed that there were negative correlations between absolute and specific AP activities, pH, and total P contents, while there were positive correlations between soil absolute and specific βG, NAG, and LAP enzyme activities, and SOC and total N contents. RDA showed that the contents of actinomycete and Gram-positive bacterium PLFA biomarkers are more closely related to the absolute and specific enzyme activities than the other PLFA biomarkers (Pfertilizer application rates to subtropical paddy soils should not exceed 44 kg P ha(-1) year(-1).

  15. Assessing long-term and rare adverse effects of medicines

    NARCIS (Netherlands)

    Duijnhoven, R.G.

    2016-01-01

    Clinical studies in the development of new medicines are primarily designed to investigate efficacy. Knowledge of adverse effects is therefore limited at the time of approval of new medicines. In this thesis several studies were conducted to investigate long-term and rare adverse effects of medicine

  16. Assessing long-term and rare adverse effects of medicines

    NARCIS (Netherlands)

    Duijnhoven, R.G.|info:eu-repo/dai/nl/357218574

    2016-01-01

    Clinical studies in the development of new medicines are primarily designed to investigate efficacy. Knowledge of adverse effects is therefore limited at the time of approval of new medicines. In this thesis several studies were conducted to investigate long-term and rare adverse effects of

  17. Marijuana effects on long-term memory assessment and retrieval.

    Science.gov (United States)

    Darley, C F; Tinklenberg, J R; Roth, W T; Vernon, S; Kopell, B S

    1977-05-01

    The ability of 16 college-educated male subjects to recall from long-term memory a series of common facts was tested during intoxication with marijuana extract calibrated to 0.3 mg/kg delta-9-tetrahydrocannabinol and during placebo conditions. The subjects' ability to assess their memory capabilities was then determined by measuring how certain they were about the accuracy of their recall performance and by having them predict their performance on a subsequent recognition test involving the same recall items. Marijuana had no effect on recall or recognition performance. These results do not support the view that marijuana provides access to facts in long-term storage which are inaccessible during non-intoxication. During both marijuana and placebo conditions, subjects could accurately predict their recognition memory performance. Hence, marijuana did not alter the subjects' ability to accurately assess what information resides in long-term memory even though they did not have complete access to that information.

  18. [Responses of soil nematode communities to long-term application of inorganic fertilizers in upland red soil].

    Science.gov (United States)

    Zhang, Wei; Liu, Man-Qiang; He, Yuan-Qiu; Fan, Jian-Bo; Chen, Yan

    2014-08-01

    Soil biota plays a key role in ecosystem functioning of red soil. Based on the long-term inorganic fertilization field experiment (25-year) in an upland red soil, the impacts of different inorganic fertilization managements, including NPK (nitrogen, phosphorus and potassium fertilizers), NPKCaS (NPK plus gypsum fertilizers), NP (nitrogen and phosphorus fertilizers), NK (nitrogen and potassium fertilizers) and PK (phosphorus and potassium fertilizers), on the assemblage of soil nematodes during the growing period of peanut were investigated. Significant differences among the treatments were observed for total nematode abundance, trophic groups and ecological indices (P NPKCaS > NPK > NP > NK. The total number of nematodes was significantly higher in NPKCaS and PK than in NPK, NP and NK except in May. Plant parasitic nematodes were the dominant trophic group in all treatments excepted in NPKCaS, and their proportion ranged between 38% and 65%. The dominant trophic group in NPKCaS was bacterivores and represented 42.1%. Furthermore, the higher values of maturity index, Wasilewska index and structure index in NPKCaS indicated that the combined application of NPK and gypsum could remarkably relieve soil acidification, resulting in a more mature and stable soil food web structure. While, that of the NK had the opposite effect. In conclusion, our study suggested that the application of both gypsum and phosphate is an effective practice to improve soil quality. Moreover, the analysis of nematode assemblage is relevant to reflect the impact of different inorganic fertilizer on the red soil ecosystem.

  19. Significant alteration of soil bacterial communities and organic carbon decomposition by different long-term fertilization management conditions of extremely low-productivity arable soil in South China.

    Science.gov (United States)

    Xun, Weibing; Zhao, Jun; Xue, Chao; Zhang, Guishan; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-06-01

    Different fertilization managements of red soil, a kind of Ferralic Cambisol, strongly affected the soil properties and associated microbial communities. The association of the soil microbial community and functionality with long-term fertilization management in the unique low-productivity red soil ecosystem is important for both soil microbial ecology and agricultural production. Here, 454 pyrosequencing analysis of 16S recombinant ribonucleic acid genes and GeoChip4-NimbleGen-based functional gene analysis were used to study the soil bacterial community composition and functional genes involved in soil organic carbon degradation. Long-term nitrogen-containing chemical fertilization-induced soil acidification and fertility decline and significantly altered the soil bacterial community, whereas long-term organic fertilization and fallow management improved the soil quality and maintained the bacterial diversity. Short-term quicklime remediation of the acidified soils did not change the bacterial communities. Organic fertilization and fallow management supported eutrophic ecosystems, in which copiotrophic taxa increased in relative abundance and have a higher intensity of labile-C-degrading genes. However, long-term nitrogen-containing chemical fertilization treatments supported oligotrophic ecosystems, in which oligotrophic taxa increased in relative abundance and have a higher intensity of recalcitrant-C-degrading genes but a lower intensity of labile-C-degrading genes. Quicklime application increased the relative abundance of copiotrophic taxa and crop production, although these effects were utterly inadequate. This study provides insights into the interaction of soil bacterial communities, soil functionality and long-term fertilization management in the red soil ecosystem; these insights are important for improving the fertility of unique low-productivity red soil.

  20. Soil ionomic and enzymatic responses and correlations to fertilizations amended with and without organic fertilizer in long-term experiments

    Science.gov (United States)

    Feng, Xumeng; Ling, Ning; Chen, Huan; Zhu, Chen; Duan, Yinghua; Peng, Chang; Yu, Guanghui; Ran, Wei; Shen, Qirong; Guo, Shiwei

    2016-04-01

    To investigate potential interactions between the soil ionome and enzyme activities affected by fertilization with or without organic fertilizer, soil samples were collected from four long-term experiments over China. Irrespective of variable interactions, fertilization type was the major factor impacting soil ionomic behavior and accounted for 15.14% of the overall impact. Sampling site was the major factor affecting soil enzymatic profile and accounted for 34.25% of the overall impact. The availabilities of Pb, La, Ni, Co, Fe and Al were significantly higher in soil with only chemical fertilizer than the soil with organic amendment. Most of the soil enzyme activities, including α-glucosidase activity, were significantly activated by organic amendment. Network analysis between the soil ionome and the soil enzyme activities was more complex in the organic-amended soils than in the chemical fertilized soils, whereas the network analysis among the soil ions was less complex with organic amendment. Moreover, α-glucosidase was revealed to generally harbor more corrections with the soil ionic availabilities in network. We concluded that some of the soil enzymes activated by organic input can make the soil more vigorous and stable and that the α-glucosidase revealed by this analysis might help stabilize the soil ion availability.

  1. Long-term Advertising Effects and Optimal Budgeting

    DEFF Research Database (Denmark)

    Hansen, Flemming; Bech Christensen, Lars

    2004-01-01

    Using pure single-source data, this paper provides evidence for theexistence and magnitude of long-term advertising effects across FMCG productcategories. Furthermore, we focus on the difficulties that arise for wellestablishedbrands when new products are introduced into the market andproduct...

  2. The Long-Term Effects of Youth Unemployment

    Science.gov (United States)

    Mroz, Thomas A.; Savage, Timothy H.

    2006-01-01

    Using NLSY data, we examine the long-term effects of youth unemployment on later labor market outcomes. Involuntary unemployment may yield suboptimal investments in human capital in the short run. A theoretical model of dynamic human capital investment predicts a rational "catch-up" response. Using semiparametric techniques to control for the…

  3. Effects of Acute Exercise on Long-Term Memory

    Science.gov (United States)

    Labban, Jeffrey D.; Etnier, Jennifer L.

    2011-01-01

    In this study, we tested the effect of acute exercise on long-term memory, specifically the timing of exercise relative to the memory challenge. We assessed memory via paragraph recall, in which participants listened to two paragraphs (exposure) and recounted them following a 35-min delay. Participants (n = 48) were randomly assigned to one of…

  4. Effects of Acute Exercise on Long-Term Memory

    Science.gov (United States)

    Labban, Jeffrey D.; Etnier, Jennifer L.

    2011-01-01

    In this study, we tested the effect of acute exercise on long-term memory, specifically the timing of exercise relative to the memory challenge. We assessed memory via paragraph recall, in which participants listened to two paragraphs (exposure) and recounted them following a 35-min delay. Participants (n = 48) were randomly assigned to one of…

  5. N Mineralization as Affected by Long-Term N Fertilization and Its Relationship with Crop N Uptake

    Institute of Scientific and Technical Information of China (English)

    YAN De-Zhi; WANG De-Jian; SUN Rui-Juan; LIN Jing-Hui

    2006-01-01

    A field experiment established in 1997 was conducted to study the effect of long-term N fertilizer application on N mineralization in a paddy soil determined using a laboratory anaerobic incubation followed with a field incubation and to measure the relationship between in situ N mineralization and crop N uptake. To estimate N mineralization in the laboratory, soil samples were collected from plots with N application at different rates for six years and were incubated.Soils treated with fertilizer N mineralized more N than unfertilized soils and mineralization increased with N application rates. Also, the fraction of total N mineralized increased with increasing N fertilizer application. These findings meant that a substantial portion of previously applied N could be recovered slowly over time in subsequent crops. The field incubation of the plot receiving no fertilizer N showed that the NH4+-N concentration varied greatly during the rice-growing season and seasonal changes of N mineralization were due more to accumulation of NH4+-N than NO3--N. Rice N uptake increased up to a maximum of 82 kg N ha-1 during the season. The close agreement found between in situ N mineralization and rice N uptake suggested that the measurement of in situ N mineralization could provide useful recommendations for adequate fertilizer N application.

  6. Effect of Long-term Fertilization on Soil Organic Carbon and Soil Inorganic Carbon in Oasis Cropland%长期施肥对绿洲农田土壤有机碳和无机碳的影响

    Institute of Scientific and Technical Information of China (English)

    荣井荣; 李晨华; 王玉刚; 唐立松; 陈效民

    2012-01-01

    以中国科学院阜康荒漠生态站的绿洲农田养分循环长期定位试验(始于1990年)为研究平台,研究了无施肥处理(CK)、单施化肥处理(NPK)、有机/无机配施处理(NPKM)和秸秆还田处理(NPKS)下,土壤无机碳(SIC)和有机碳(SOC)在剖面和各施肥年限的含量变化特征及其影响。结果表明:施肥、剖面层次和施肥年限对SOC与SIC含量变化影响显著(P〈0.01)。在各施肥处理中,与CK相比,NPK、NPKM和NPKS的SOC与SIC含量明显增加(P〈0.05),并且有机/无机肥配施模式下的SIC含量显著高于单施化肥模式;在剖面层次间,SIC含量从0~20cm的9.12 g/kg增加到40~60 cm的9.94 g/kg,而SOC变化趋势与之相反。表明合理施肥能够增加土壤表层有机碳含量,有机/无机配施会使耕层以下土壤无机碳增加。%In this study, the Fukang Station for Desert Ecological garded as a platform to lucubrate the dynamic change of soil carbon Research, Chinese Academy Sciences, was re- content, soil carbon sequestration potential and long-term oasis agricultural nutrient cycling, including the distribution of soil inorganic carbon content (SIC) and organic carbon content (SOC) along soil profile and at different fertilization time under the different soil fertilization treatments, such as the treatment without fertilization (CK), single fertilizer application (NPK), and fertilization treatment with straw (S) in arid area. The results showed that the fertilizer application, soil depth and fertilization time affected significantly the SOC content and SIC content in soil (P 〈 0. 01 ). Compared with CK, the SOC con- tent and SIC content under NPK, M and S were significantly increased ( P 〈 0. 05 ) , and the SIC content under the organic/inorganic fertilizing combination (M) was significantly higher than that under chemical fertilizer applica- tion. The average SIC content was increased

  7. 长期定位施肥对石灰性紫色水稻土AMF多样性的影响%Effects of long-term fertilization on arbuscular mycorrhizal fungi community in calcareous purple paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 李芳; 张小平; 涂仕华; KRISTINA Lindstr(o)m

    2012-01-01

    为了解长期定位施肥对石灰性紫色水稻土丛枝菌根真菌(AMF)物种多样性的影响,从稻麦轮作下连续26年定位施农家肥(M)、氮肥+农家肥(NM)、氮磷肥+农家肥(NPM)、氮磷钾肥+农家肥(NPKM)、不施肥(CK)、氮肥(N)、氮磷肥(NP)、氮磷钾肥(NPK)等不同施肥处理小区采集根区土样,分离鉴定AMF、测定多样性特征.共鉴定出17种AMF,其中球囊霉属Glomus 12种,占己分离总数的70.5%,为优势属;无梗囊霉属Acaulospora 3 种,占17.6%;原囊霉属Archaeospora和内养囊霉属Entrophospora各1种,各占5.9%.无论是石灰性紫色十种植水稻还是小麦,AMF侵染率最高的施肥处理均为无肥处理(CK),施肥特别是磷肥,降低AMF侵染率、孢子密度、相对多度和种丰度.变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)分析结果表明,不施肥对照(CK)的AMF多样性最丰富,多样性指数最高,水稻和小麦种植下的多样性指数分别为2.68和3.02;与无机肥处理相比,农家肥配施无机肥提高了AMF多样性指数.农家肥配施无机肥更有利于AMF发育.%To determine the influence of long term fertilization on arbuscular mycorrhizal fungi (AMF) species diversity in calcareous purplish paddy soil, rhizosphere soil samples collected from different designed plots continuously supplied with manure only (M), nitrogen fertilizer plus manure (NM), nitrogen and phosphoric fertilizer plus manure (NPM), nitrogen, phosphoric and potassium fertilizer plus manure (NPKM), mineral nitrogen (N), nitrogen-phosphoric fertilizer (NP), nitrogen and phosphoric and potassium fertilizer (NPK) and without treatment (CK), under rice-wheat rotations for 26 years were mycologically investigated. The results showed that there are 17 species of AMF, among them, 12 species belong to Glomus, accounting for 70.5 percent of the total isolated species. Three species belong to Acaulospora, accounting for 17.6 percent of the isolated species

  8. [Effect of Long-Term Fertilization on Organic Nitrogen Functional Groups in Black Soil as Revealed by Synchrotron-Based X-Ray Absorption Near-Edge Structure Spectroscopy].

    Science.gov (United States)

    Li, Hui; Gao, Qiang; Wang, Shuai; Zhu, Ping; Zhang, Jin-jing; Zhao, Yi-dong

    2015-07-01

    Nitrogen (N) is a common limiting nutrient in crop production. The N content of soil has been used as an important soil fertility index. Organic N is the major form of N in soil. In most agricultural surface soils, more than 90% of total N occurs in organic forms. Therefore, understanding the compositional characteristics of soil organic N functional groups can provide the scientific basis for formulating the reasonable farmland management strategies. Synchrotron radiation soft X-ray absorption near-edge structure (N K-edge XANES) spectroscopy is the most powerful tool to characterize in situ organic N functional groups compositions in soil. However, to our most knowledge, no studies have been conducted to examine the organic N functional groups compositions of soil using N K-edge XANES spectroscopy under long-term fertilization practices. Based on a long-term field experiment (started in 1990) in a black soil (Gongzhuling, Northeast China), we investigated the differences in organic N functional groups compositions in bulk soil and clay-size soil fraction among fertilization patterns using synchrotron-based N K- edge XANES spectroscopy. Composite soil samples (0-20 cm) were collected in 2008. The present study included six treatments: farmland fallow (FALL), no-fertilization control (CK), chemical nitrogen, phosphorus, and potassium fertilization (NPK), NPK in combination with organic manure (NPKM), 1.5 times of NPKM (1.5 NPKM), and NPK in combination with maize straw (NPKS). The results showed that N K-edge XANES spectra of all the treatments under study exhibited characteristic absorption peaks in the ranges of 401.2-401.6 and 402.7-403.1 eV, which were assigned as amides/amine-N and pyrrole-N, respectively. These characteristic absorption peaks were more obvious in clay-size soil fraction than in bulk soil. The results obtained from the semi-quantitative analysis of N K-edge XANES spectra indicated that the relative proportion of amides/amine-N was the highest

  9. Soil organic carbon dynamics under long-term fertilizations in arable land of northern China

    Science.gov (United States)

    Zhang, W. J.; Wang, X. J.; Xu, M. G.; Huang, S. M.; Liu, H.; Peng, C.

    2010-02-01

    Soil carbon sequestration is a complex process influenced by agricultural practices, climate and soil conditions. This paper reports a study of long-term fertilization impacts on soil organic carbon (SOC) dynamic from six long-term experiments. The experiment sites are located from warm-temperate zone with a double-cropping system of corn (Zea mays L.) - wheat (Triticum Aestivium L.) rotation, to mild-temperate zones with mono-cropping systems of continuous corn, or a three-year rotation of corn-wheat-wheat. Mineral fertilizer applications result in an increasing trend in SOC except in the arid and semi-arid areas with the mono-cropping systems. Additional manure application is important to maintain SOC level in the arid and semi-arid areas. Carbon conversion rate is significant lower in the warm-temperate zone with double cropping system (6.8%-7.7%) than that in the mild-temperate areas with mono-cropping systems (15.8%-31.0%). The conversion rate is significantly correlated with annual precipitation and active accumulative temperature, i.e., higher conversion rate under lower precipitation and/or temperature conditions. Moreover, soil high in clay content has higher conversion rate than soils low in clay content. Soil carbon sequestration rate ranges from 0.07 to 1.461 t ha-1 year-1 in the upland of northern China. There is significantly linear correlation between soil carbon sequestration and carbon input at most sites, indicating that these soils are not carbon-saturated thus have potential to migrate more CO2 from atmosphere.

  10. Long-term outcomes of fertility-sparing treatment of atypical polypoid adenomyoma with medroxyprogesterone acetate.

    Science.gov (United States)

    Nomura, Hidetaka; Sugiyama, Yuko; Tanigawa, Terumi; Matoda, Maki; Kanao, Hiroyuki; Kondo, Eiji; Takeshima, Nobuhiro

    2016-01-01

    Our objective was to analyze the long-term oncologic outcomes of fertility-preserving hormonal treatment with medroxyprogesterone acetate (MPA) in patients with APA. In a retrospective chart review, we identified patients with APA who were treated with MPA for fertility preservation at our hospital between 2001 and 2011. Eighteen patients with histologically diagnosed APA were identified. Clinical data including treatment, obstetrical, and oncologic outcomes were recorded. The mean observation period was 77.6 months (median 73.5, range 22-142), and the mean age was 33.6 years. Four patients also developed well-differentiated endometrial carcinoma. After the treatment, 14 patients (77.8 %) achieved either a complete response or partial response. Eight patients experienced recurrence, while four experienced persistent disease. Ten patients (55.6 %) eventually underwent hysterectomy. The median time to hysterectomy was 40.3 months (range 24-68). Nine patients progressed to endometrial cancer, and one experienced persistent APA. Among younger patients (<35 years of age), four out of five patients who were married could have children. Seven patients (38.9 %) showed no evidence of the disease during the observation period (median 60 months, range 22-117 months). No one died because of the disease during the observation period. MPA yields a high response rate in APA, and if only younger patients are considered, a favorable pregnancy rate can be obtained. However, because recurrence rate is high, long-term follow-up under supervision of a trained gynecologic oncologist is required. To confirm MPA's utility, multi-center collaboration would be warranted.

  11. Scenario Analysis on Effects of Long-term Fertilization on Soil Carbon and Nitrogen Codependency%长期定位施肥对土壤的碳氮共济效应情景分析

    Institute of Scientific and Technical Information of China (English)

    雷宝坤; 刘宏斌; 陈安强; 毛妍婷; 续勇波

    2014-01-01

    The term of carbon (C) and nitrogen (N) codependency, reflecting the relation of mutual dependence, co-transformation and cooperation, is regarded as active factors for improving soil quality, which differs it from the passive couple mechanism for discussing the soil C and N relationship. There was an interrelation of mutual dependence and interaction between C and N in soil. What quantity and composition of soil C and N could facilitate the codependency of C and N? How much soil N could be sustained by soil C? These problems deserve further consideration. The paper analysed the change in soil C and N concentrations, effects of fertilization on the soilw(C)/w(N) ratio, soil capacity of conserving N by C, the relationship of soil C and N codependency and its scenario analysis by data mining the long-term fertilization experiment results to explore the biologic potential of soil C and N, improve soil productivity, environment and balanced cycling of soil C and N. By searching literature database, we obtained about 1782 long-term fertilization data on carbon and nitrogen in China soil from 69 representative articles. Results from analyzing these data sets indicated that the correlation between organic C and total N could be expressed by the functionyC=7.66xN+1.8162 (r2=0.734**,n=737). The mean concentrations of total N and organic C were 1.17 g⋅kg-1 and 10.8 g⋅kg-1, and ranged from 0.08 g⋅kg-1 to 3.52 g⋅kg-1 and from 0.64 g⋅kg-1 to 32.08 g⋅kg-1, respectively. Carbon to nitrogen ratio (w(C)/w(N)) concentrated on the range from 7.6 to 10.7, accounting for 80% of the total samples. It was helpful to increasew(C)/w(N) through fertilizing inorganic and organic fertilizer together. Solely fertilizing synthesized fertilizers, especially only one fertilizer, decreasedw(C)/w(N) significantly. Under the scenario of the storage rate of 20 kg N·hm-2·a-1 and the targetw(C)/w(N) of 9, 10 and 11, the soil samples of carbon saturation accounted for 52.7%, 72.1% and 87

  12. Effects of Long-term Fertilization on Enzyme Activities and Soil Fertility for Black Farmlands Under Different Soil Matter Levels%长期施肥对不同有机质含量农田黑土土壤酶活性及土壤肥力的影响

    Institute of Scientific and Technical Information of China (English)

    陈文婷; 付岩梅; 隋跃宇; 刘晓冰; 李建维

    2013-01-01

    The research investigated the effects of long-term fertilization on soil enzyme activities and soil fertility for the black farmlands under different soil organic matter levels. This study used the conventional analysis methods to test and analyze the activity of soil urease, phosphatase, invertase, protease and the contents of soil organic matter, total nitrogen, total phosphorus, available nitrogen, available phosphorus in five black farmlands soil with different soil matter content of soil spatial shift long-term experiments in National Observation Station of Hailun Agro-ecology System. The results showed that, the application of chemical fertilizers could increase the nutrient content in different degree and soil enzyme activities of black soil. The order of the raise was Bei'an (SOM11)>Nenjiang (SOM6)>Helen (SOM5)>Dehui (SOM3) > Lishu (SOM1.7). Compared to other four soils, Bei'an (SOM11) reached significant difference level(P嫩江(SOM6)>海伦(SOM5)>德惠(SOM3)>梨树(SOM1.7),北安黑土与其他4种土壤之间达到了差异显著水平(P<0.05)。相关分析结果显示:土壤脲酶、磷酸酶、蛋白酶、蔗糖酶与土壤有机质、全氮、全磷、碱解氮显著相关,土壤脲酶、蔗糖酶可以反映不同有机质含量农田黑土长期施肥后土壤质量变化趋势。

  13. Bacterial community structure and diversity in a black soil as affected by long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    WEI Dan; YANG Qian; ZHANG Jun-Zheng; WANG Shuang; CHEN Xue-Li; ZHANG Xi-Lin; LI Wei-Qun

    2008-01-01

    Black soil (Mollisol) is one of the main soil types in northeastern China.Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis (PCR-DGGE) methods were used to examine the influence of various fertilizer combinations on the structure and function of the bacterial community in a black soil collected from Harbin,Heilongjiang Province.Biolog results showed that substrate richness and catabolic diversity of the soil bacterial community were the greatest in the chemical fertilizer and chemical fertilizer+manure treatments.The metabolic ability of the bacterial community in the manure treatment was similar to the control.DGGE fingerprinting indicated similarity in the distribution of most 16S rDNA bands among all treatments,suggesting that microorganisms with those bands were stable and not influenced by fertilization.However,chemical fertilizer increased the diversity of soil bacterial community.Principal component analysis of Biolog and DGGE data revealed that the structure and function of the bacterial community were similar in the control and manure treatments,suggesting that the application of manure increased the soil microbial population,but had no effect on the bacterial community structure.Catabolic function was similar in the chemical fertilizer and chemical fertilizer+manure treatments,but the composition structure of the soil microbes differed between them.The use of chemical fertilizers could result in a decline in the catabolic activity of fast-growing or eutrophic bacteria.

  14. [Acute and long-term effects of ecstasy

    OpenAIRE

    Salzmann, Julie; Marie-Claire, Cynthia; Noble, Florence

    2004-01-01

    International audience; Side effects in the short term Recreational use of Ecstasy (3,4-methylenedioxymethamphetamine or MDMA), a synthetic drug, has considerably increased over the last decade. Since its appearance it is associated with the rave culture, but its use has spread to other social settings. The drug produces euphoria and empathy, but can lead to side effects, notably acute, potentially lethal, toxicity (malignant hyperthermia and/or hepatitis). Neurotoxicity in the long-term More...

  15. Effect of Long-term Different Fertilization Ways on Soil Enzyme Activities and Fertility in Dryland Black Humus Soil in the Loess Plateau%长期不同施肥方式对黄土高原旱地黑垆土土壤酶活性及其肥力的影响

    Institute of Scientific and Technical Information of China (English)

    张平良; 王淑英; 姜小凤; 苏敏; 李倩

    2009-01-01

    以30 a(1979~2008)肥料长期定位试验为基础,分析探讨长期不同施肥方式对旱地黑垆土耕层(0~20 cm)土壤酶活性及其肥力的影响.结果表明:土壤脲酶活性M处理显著高于其他处理,MNP和SNP处理效果优于NP处理;土壤多酚氧化酶活性N和NP处理增加效果显著,M、MNP、SNP处理效果均不明显;土壤蛋白酶活性N处理效果最佳,显著高于其他处理;MNP、SNP处理能显著增加土壤有机质和全磷含量,有利于全氮含量的积累,表明有机-无机肥配施是旱地中低产田培肥土壤的有效措施.%By a 30-year (1979~2008) long-term located fertilizer experiment, effect of long-term different fertilization ways on soil enzyme activities and fertility in dryland black humus soil was analyzed. The results showed that, effect of M treatment generate on soil urease activity is obviously higher than other treatments, and the effect of MNP and SNP treatments generate surpass that of NP treatment; The effect of N and NP treatments generate increasing on soil polyphenoloxidase activity is remarkable, and effect of M, MNP and SNP treatments generate is not to be obvious. The effect of N treatment way on soil protein enzyme activity is very best, which obviously is higher than others; MNP and SNP treatments can obviously increase soil organic and total phosphorus contents, which is advantage to accumulate total nitrogen content, which indicated that organic-inorganic matches executes is a effective measure of the cultivating soil fertility in dryland of middle-low yielding.

  16. [Acute and long-term effects of ecstasy].

    Science.gov (United States)

    Salzmann, Julie; Marie-Claire, Cynthia; Noble, Florence

    2004-10-23

    Side effects in the short term Recreational use of Ecstasy (3,4-methylenedioxymethamphetamine or MDMA), a synthetic drug, has considerably increased over the last decade. Since its appearance it is associated with the rave culture, but its use has spread to other social settings. The drug produces euphoria and empathy, but can lead to side effects, notably acute, potentially lethal, toxicity (malignant hyperthermia and/or hepatitis). Neurotoxicity in the long-term Moreover, MDMA has been shown to induce long-term deleterious effects and provoke neurotoxic affecting the serotoninergic system. However, the psychopathological consequences of such neurotoxicity are still controversial, particularly since many ecstasy consumers are multi-drug users. A complex pharmacological profile The mechanism of action of MDMA involves various neurobiological systems (serotonin, dopamine, noradrenalin), that may all interact.

  17. Community analysis of arbuscular mycorrhizal fungi and bacteria in the maize mycorrhizosphere in a long-term fertilization trial.

    Science.gov (United States)

    Toljander, Jonas F; Santos-González, Juan C; Tehler, Anders; Finlay, Roger D

    2008-08-01

    In this study, we investigated the impact of organic and mineral fertilizers on the community composition of arbuscular mycorrhizal (AM) fungi and bacteria in the mycorrhizosphere of maize in a field experiment established in 1956, in south-east Sweden. Roots and root-associated soil aggregates were sampled four times during the growing season in 2005, in control plots and in plots amended with calcium nitrate, ammonium sulphate, green manure, farmyard manure or sewage sludge. Fungi in roots were identified by cloning and sequencing, and bacteria in soil aggregates were analysed by terminal-restriction fragment length polymorphism, cloning and sequencing. The community composition of AM fungi and bacteria was significantly influenced by the different fertilizers. Changes in microbial community composition were mainly correlated with changes in pH induced by the fertilization regime. However, other factors, including phosphate and soil carbon content, also contributed significantly to these changes. Changes in bacterial community composition and a reduction in bacterial taxon richness throughout the growing season were also manifest. The results of this study highlight the importance and significant effects of the long-term application of different fertilizers on edaphic factors and specific groups of fungi and bacteria playing a key role in arable soils.

  18. Long-term Advertising Effects and Optimal Budgeting

    OpenAIRE

    Hansen, Flemming; Bech Christensen, Lars

    2004-01-01

    Using pure single-source data, this paper provides evidence for the existence and magnitude of long-term advertising effects across FMCG product categories. Furthermore, we focus on the difficulties that arise for wellestablished brands when new products are introduced into the market and product innovations take place. Our research shows that such occurrences drastically alter the relationship between share of voice and share of market in any given FMCG market, hence making...

  19. The Long Term Effects of Legalizing Divorce on Children

    OpenAIRE

    Gonzalez, Libertad; Viitanen, Tarja

    2008-01-01

    We estimate the effect of divorce legalization on the long-term well-being of children. Our identification strategy relies on exploiting the different timing of divorce legalization across European countries. Using European Community Household Panel data, we compare the adult outcomes of cohorts who were raised in an environment where divorce was banned with cohorts raised after divorce was legalized in the same country. We also have "control" countries where all cohorts were exposed (or not ...

  20. Long-term N fertilization and conservation tillage practices conserve surface but not profile SOC stocks under semi-arid irrigated corn

    Science.gov (United States)

    No tillage (NT) and N fertilization can increase surface soil organic C (SOC) stocks, but the effects deeper in the soil profile are uncertain. Subsequent tillage could counter SOC stabilized through NT practices by disrupting soil aggregation and promoting decomposition. We followed a long-term ti...

  1. Long-term neurotoxic effects of dimethylamine borane intoxication.

    Science.gov (United States)

    Liu, Chi-Hung; Wang, Hsuan-Min; Lin, Kun-Ju; Kuo, Hung-Chou; Weng, Yi-Hsin; Shih, Tung-Sheng; Huang, Chin-Chang

    2012-08-15

    To investigate the long-term neurotoxic effects in a patient with acute dimethylamine borane (DMAB) intoxication. A 38-year-old man, working in a semiconductor factory, with acute DMAB intoxication presented with confusion, and drowsiness, followed by cognitive impairments and motor-predominant axonal polyneuropathy. We performed serial neurobehavioral assessments and functional neuroimaging studies, including brain (99m)Tc-TRODAT single photon emission computed tomography (SPECT) and brain positron emission tomography (PET) scan to monitor the long-term central nervous system (CNS) effects of DMAB intoxication. Neurobehavioral tests revealed a persistent impairment in episodic memory of visual retention semantic category retrieval and working memory of digit span (backward). Brain (99m)Tc-TRODAT SPECT scan showed a lower radioactivity uptake in the left striatum and F-18 FDG PET scan revealed a relatively decreased cerebral metabolism at the anterior cingulate gyrus and both frontal regions. Follow-up neurobehavioral tests showed that the cognitive improvements were mainly documented in intelligence, attention function, conceptual shift, perceptual motor speed, verbal learning and working memory but were limited in visual memory and executive functions. Patients with acute DMAB intoxication may have a long-lasting CNS toxicity on the cognitive dysfunction, parkinsonism, and an impaired metabolic activity of the brain. Clinical improvements may sustain during the long-term follow-up period. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. The Long-Term Effect of Childhood Poverty

    DEFF Research Database (Denmark)

    Lesner, Rune Vammen

    This paper uses variation among siblings to identify the effect of childhood poverty on long-term outcomes such as income, earnings, job type, employment, and having children. Childhood poverty is found to have large negative effects on labour market outcome and small effects on non-labour market...... outcomes. The marginal effect of one additional year of childhood poverty from the age of 13 to 15 is found to decrease the disposable income of the individual by 6.4% around the age of 30. The effect size is found to have an inverse u-shape in the age of the child, peaking in the early teens...

  3. 长期不同施肥对(土娄)土团聚体胶结剂的影响%Effects of long-term fertilization regimes on changes of aggregate cementing agent of Lou Soil

    Institute of Scientific and Technical Information of China (English)

    薛彦飞; 薛文; 张树兰; 杨学云

    2015-01-01

    密度以及游离氧化铝含量,但是六碳糖、碳酸钙、粘粒、游离氧化铁含量与CK没有差N. 长期不施氮或不施磷处理与CK相比,土壤五碳糖、六碳糖、碳酸钙以及游离氧化铁的含量显著提高,但游离氧化铝含量显著降低,而对菌丝和粘粒含量没有影响. 不同团聚体胶结剂与团聚体平均重量直径的线性相关分析表明,机械稳定性团聚体平均重量直径与碳酸钙含量呈极显著正相关、与游离氧化铁显著正相关,与五碳糖和六碳糖极显著负相关. 水稳性团聚体平均重量直径分别与菌丝密度、 碳酸钙极显著正相关,与游离氧化铁显著正相关,与五碳糖达显著负相关. [结论]团聚体胶结剂与平均重量直径的多元逐步回归分析表明,碳酸钙是影响(土娄)土团聚体稳定性唯一显著的胶结剂.%[Objectives] Soil aggregate is a basic unit of soil structure , its formation and stability is mainly related to soil cementation of various cementing agent which is affected by soil management regimes .Fertilization practice , as one of soil management regimes has an important effect on aggregate cementing agent due to different input levels and subsequent effects on crop production .This study investigated effects of different fertilization regimes on aggregate cementing agent and was to thereby understand mechanism of formation and distribution of aggregates in Lou soil based on a long-term experiment under winter wheat and summer maize cropping system in Guanzhong Plain, Shaanxi province , China.[Methods] Different fertilization regimes included control ( CK, no nutrient input), nitrogen only (N), nitrogen and potassium (NK), phosphorus and potassium (PK), NP, NPK and straw plus NPK ( SNPK) and two levels of manure plus NPK ( M1NPK and M2NPK), totally nine treatments.The determination of aggregate cementing agents included fungal hyphal density , pentose , hexose , calcium carbonate , clay, free iron oxide and

  4. INFLUENCE OF LONG TERM APPLICATION OF FERTILIZERS ON SOIL ORGANIC MATTER CONTENT

    Directory of Open Access Journals (Sweden)

    K.V. Naga Madhuri

    2013-06-01

    Full Text Available The soil samples were collected from the soils of Long Term Fertilizer Experiments that have been fertilized for the last 25 years from a control plot (receiving no fertilizer/FYM; b plot receiving 100% NPK fertilizer application and c Plot receiving 100% N in the form of FYM, to study the changes in nature and amount of organic matter and these were compared with a similar adjacent soil under natural vegetation. The soil samples were collected from 0-15 cm (surface and 15-30 cm (sub surface layers. The humic substances were fractionated by Tyurins method. The total N and available N content was determined and C/N ratio was calculated. The humic acid was isolated, purified and analyzed for oxygen containing functional groups and spectral properties. It was observed that the soil under natural vegetation had a higher total N while the soil under continuous cultivation had higher available N. The C/N ratio of soil under natural vegetation was high compared to the soil under continuous cultivation. These values were high in surface layers compare to sub surface layers. The oxygen containing functional groups in Humic acid (HA were high in soil under natural vegetation compared to the soil under continuous cultivation. The total acidity and COOH content of surface layers was high compared to sub surface layers in soils under both situations. Phenolic OH groups of subsurface layer was high in soil under natural vegetation and continuous cultivation indicating that this group in sub surface layers and high potential for interaction with clays and metal ions. The higher contents of total acidity and –COOH groups in soil under natural vegetation could be attributed to the difference in chemical composition and molecular weight of humic substances. The E4/E6 ratios of HA’S were less than 5.0 indicating high degree of condensation of aromatic humic acid. The potentiometric titrations of humic acids with standard 0.1 N NaOH indicated a gradual increase

  5. Carbon Sequestration in Soil Humic Substances Under Long-Term Fertilization in a Wheat-Maize System from North China

    Institute of Scientific and Technical Information of China (English)

    SONG Xiang-yun; LIU Shu-tang; LIU Qing-hua; ZHANG Wen-ju; HU Chun-guang

    2014-01-01

    The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (WSS), humic acid (HA), fulvic acid (FA) and humin (HU) were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were signiifcant different among the treatments with manure. A signiifcant correlation was found between the increased soil organic carbon (SOC) and HS (R2=0.98, P<0.01). The change in the E4/E6 ratio was signiifcantly correlated with the increased SOC (R2=0.88, P<0.01), HA (R2=0.91, P<0.01), FA (R2=0.91, P<0.01) and HU (R2=0.88, P<0.01). The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization.

  6. Genetic diversity of indigenous soybean-nodulating rhizobia in response to locally-based long term fertilization in a Mollisol of Northeast China.

    Science.gov (United States)

    Yan, Jun; Chen, WenFeng; Han, XiaoZeng; Wang, EnTao; Zou, WenXiu; Zhang, ZhiMing

    2017-01-01

    The influences of five different fertilizer treatments on diversity of rhizobia in soybean nodule were investigated in a long-term experiment with with four replicates: (1) control (without fertilization), (2) balanced NPK fertilizer (NPK), and (3-5) unbalanced chemical fertilizers without one of the major elements (NP, PK, and NK) in Mollisol in Northeast China. The highest soybean yield was observed in the NPK treatment. Total of 200 isolates were isolated and grouped into four Bradyrhizobium genospecies corresponding to B. japonicum, B. diazoefficiens, B. ottawaense and Bradyrhizobium sp. I, based upon the multilocus sequence analysis of 6 housekeeping genes. The Bradyrhizobium sp. I was extensively distributed throughout the study site and was recorded as the dominant soybean rhizobia (82.5-87.5%). Except the NK treatment, the other fertilizer treatments had no effect on rhizobial species composition. Compared with the CK treatment, all the fertilizer treatments decreased species richness, diversity and evenness. The soil organic carbon contents, available N content and pH were the key soil factors to rhizobial community structure. Results suggest that long-term fertilization can decrease rhizobial species diversity, while balanced fertilization with NPK is the most suitable fertilization regime if taking both soybean yields and rhizobial diversity into account.

  7. Cadmium levels in soils and plants from some long-term soil fertility experiments in the United States of America

    Energy Technology Data Exchange (ETDEWEB)

    Mortvedt, J.J.

    Phosphate fertilizers contain varying amounts of Cd and other heavy metals as contaminants from phosphate rock (PR). To determine whether periodic applications of P fertilizers resulted in measurable accumulations of Cd in soils and in harvested crops, soil and plant tissue samples from nine long-term (>50 yr) soil fertility experiments in the USA were analyzed for Cd, as well as P and other elements. Annual Cd rates were estimated to range from 0.3 to 1.2 g ha/sup -1/ in these experiments. Plant tissues analyzed were corn (Zea mays L.), soybean (Glycine max L. Merr.), and wheat (Triticum aestivum L.) leaves or grain, and timothy (Phleum pratense L.) forage. Results from these long-term experiments have shown that plant uptake of Cd contaminants in P fertilizers containing < 10 mg Cd kg/sup -1/ is negligible. While the Cd accumulations in soil in these experiments could not be calculated, they would approximate that accumulated in most agricultural soils in the USA at this time. About 70% of the P fertilizers is produced from Florida PR, which contains <10 mg kg/sup -1/ of Cd, as compared with about 10% from the western USA, which contains higher Cd levels. Therefore, adding Cd to soils as a contaminant in P fertilizers at rates ranging from 0.3 to 1.2 g Cd ha/sup -1/ does not appear to result in increased Cd levels in plants as a result of long-term P fertilization.

  8. Plant and soil fungal but not soil bacterial communities are linked in long-term fertilized grassland

    Science.gov (United States)

    Cassman, Noriko A.; Leite, Marcio F. A.; Pan, Yao; de Hollander, Mattias; van Veen, Johannes A.; Kuramae, Eiko E.

    2016-03-01

    Inorganic fertilization and mowing alter soil factors with subsequent effects-direct and indirect - on above- and below-ground communities. We explored direct and indirect effects of long-term fertilization (N, P, NPK, Liming) and twice yearly mowing on the plant, bacterial and fungal communities and soil factors. We analyzed co-variation using 16S and 18S rRNA genes surveys, and plant frequency and edaphic factors across treatments. The plant and fungal communities were distinct in the NPK and L treatments, while the bacterial communities and soil factors were distinct in the N and L treatments. Plant community diversity and evenness had low diversity in the NPK and high diversity in the liming treatment, while the diversity and evenness of the bacterial and fungal communities did not differ across treatments, except of higher diversity and evenness in the liming treatment for the bacteria. We found significant co-structures between communities based on plant and fungal comparisons but not between plant and bacterial nor bacterial and fungal comparisons. Our results suggested that the plant and fungal communities are more tightly linked than either community with the bacterial community in fertilized soils. We found co-varying plant, bacterial and fungal taxa in different treatments that may indicate ecological interactions.

  9. Evaluation of the CENTURY model using long-term fertilization trials under corn-wheat cropping systems in the typical croplands of China.

    Science.gov (United States)

    Cong, Rihuan; Wang, Xiujun; Xu, Minggang; Ogle, Stephen M; Parton, William J

    2014-01-01

    Soil organic matter models are widely used to study soil organic carbon (SOC) dynamics. Here, we used the CENTURY model to simulate SOC in wheat-corn cropping systems at three long-term fertilization trials. Our study indicates that CENTURY can simulate fertilization effects on SOC dynamics under different climate and soil conditions. The normalized root mean square error is less than 15% for all the treatments. Soil carbon presents various changes under different fertilization management. Treatment with straw return would enhance SOC to a relatively stable level whereas chemical fertilization affects SOC differently across the three sites. After running CENTURY over the period of 1990-2050, the SOC levels are predicted to increase from 31.8 to 52.1 Mg ha-1 across the three sites. We estimate that the carbon sequestration potential between 1990 and 2050 would be 9.4-35.7 Mg ha-1 under the current high manure application at the three sites. Analysis of SOC in each carbon pool indicates that long-term fertilization enhances the slow pool proportion but decreases the passive pool proportion. Model results suggest that change in the slow carbon pool is the major driver of the overall trends in SOC stocks under long-term fertilization.

  10. 宁远县耕地地力变化状况与施肥效益的长期定位监测研究%Long-term Located Monitoring in Fertility Variation and Fertilizing Effects of Cultivated Land in Ningyuan County

    Institute of Scientific and Technical Information of China (English)

    蒋毛庚; 柏小勇; 胡萍翠; 陈志翠

    2011-01-01

    总结分析了1999~2007年宁远县水稻土的土壤肥力监测、肥力试验及农户施肥效果.结果表明:9a间土壤中有机质平均含量下降1g/kg,不同土种区域有机质含量变化差异较大,浅黄泥等土种有机质含量平均上升了5.1g/kg,河沙泥等土种减少了4.7g/kg;监测区域内约有25.6%的耕地肥力水平逐年上升,有53.3%的耕地土壤肥力呈下降的趋势;长期不施任何肥料情况下,地力产量为施肥区的64.3%,并且产量有下降的趋势,不施肥严重影响作物产量的提高;30%有机肥与70%无机肥的配合施用为最佳配施比例.最后撤道了利用该监测成果指导全县大面积的配方施肥和农作物秸秆还田所取得的成效.%The results of monitoring and experiment of rice soil fertility and fertilizing effects of farmer in Ningyuan County in 1999~2007 were summarized and analyzed.The results indicated that the average content of organic matters in soil decreased 1 g/kg; the content of organic matters in different soil types changed significantly, in which, the content of organic mauers in six soil types (shallow yellow mud, etc.) averagely increased 5.1 g/kg, and that in five soil types (river sediment, etc.) averagely decreased 4.7 g/kg; within the monitoring area, 25.6% of cultivated land fertility increased year by year, and 53.5% of cultivated land fertility showed decreasing trend; under the condition that non fertilizer application for a long-term, the capability yield in this area was the 64.3% of that in fertilizer application area.and the yield had decreasing trend, therefore, non fertilizer application will seriously impact the increase of crop yield; 30% of organic fertilizer combined applying with 70% of inorganic fertilizer is the optirmum formula for fertilizing.In the end, the strategy that using this monitoring results to enhance soil fertility and the achievements that using this monitoring results to guide formula fertilizing in

  11. Factors affecting potassium fixation in seven soils under 15-year long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    ZHANG HuiMin; XU MingGang; ZHANG WenJu; HE XinHua

    2009-01-01

    Potassium (K) fixation by seven soils, including black soil, fluvo-aquic soil, grey desert soil, loess soil, paddy soil, red soil and purple soil, was determined by laboratory simulation under a fifteen-year-pe-riod of long-term fertilization. Factors affecting soil K fixation were then discussed by factor analysis and stepwise regression. Magnitude of soil K fixation rate was as follows: the black soil > the purple soil > the loess soil > the fluvo-aquic soil > the paddy soil > the grey desert soil > the red soil. Our re-sulta showed that soil K fixation capacity was significantly affected by the clay mineral types in the soils. Potassium fixation capacity of soils, whose 2:1 layer silicates were dominant minerals, was af-fected by two components extracted by the method of principal component analysis: the first including soil available K, slow available K and K+ saturation, and the second including cation exchange capacity (CEC), soil organic matter (SOM) and <0.002 mm clay contents. Potassium fixation rate was mainly af-fected by K+ saturation and CEC with lower added K concentration (from 0.4 to 1.6 g/L), and by K+ saturation and <0.002 mm clay content with higher added K concentration (from 2.4 to 4.0 g/L).

  12. Long-term health effects among testicular cancer survivors.

    Science.gov (United States)

    Hashibe, Mia; Abdelaziz, Sarah; Al-Temimi, Mohammed; Fraser, Alison; Boucher, Kenneth M; Smith, Ken; Lee, Yuan-Chin Amy; Rowe, Kerry; Rowley, Braden; Daurelle, Micky; Holton, Avery E; VanDerslice, James; Richiardi, Lorenzo; Bishoff, Jay; Lowrance, Will; Stroup, Antoinette

    2016-12-01

    Testicular cancer is diagnosed at a young age and survival rates are high; thus, the long-term effects of cancer treatment need to be assessed. Our objectives are to estimate the incidence rates and determinants of late effects in testicular cancer survivors. We conducted a population-based cohort study of testicular cancer survivors, diagnosed 1991-2007, followed up for a median of 10 years. We identified 785 testicular cancer patients who survived ≥5 years and 3323 men free of cancer for the comparison group. Multivariate Cox regression analysis was used to compare the hazard ratio between the cases and the comparison group and for internal analysis among case patients. Testicular cancer survivors experienced a 24 % increase in risk of long-term health effects >5 years after diagnosis. The overall incidence rate of late effects among testicular cancer survivors was 66.3 per 1000 person years. Higher risks were observed among testicular cancer survivors for hypercholesterolemia, infertility, and orchitis. Chemotherapy and retroperitoneal lymph node dissection appeared to increase the risk of late effects. Being obese prior to cancer diagnosis appeared to be the strongest factor associated with late effects. Testicular cancer survivors were more likely to develop chronic health conditions when compared to cancer-free men. While the late effects risk was increased among testicular cancer survivors, the incidence rates of late effects after cancer diagnosis was fairly low.

  13. Soil phosphorus dynamic, balance and critical P values in long-term fertilization experiment in Taihu Lake region, China

    Institute of Scientific and Technical Information of China (English)

    SHI Lin-lin; SHEN Ming-xing; LU Chang-yin; WANG Hai-hou; ZHOU Xin-wei; JIN Mei-juan; WU Tong-dong

    2015-01-01

    Phosphorus (P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment (started 1980) to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen (N) and potassium (K), only the folowing treatments were chosen for subsequent discussion, including: C0 (control treatment without any fertilizer or organic manure), CNK treatment (mineral N and K only), CNPK (balanced fertilization with mineral N, P and K), MNK (integrated organic ma-nure and mineral N and K), and MNPK (organic manure plus balanced fertilization). The results revealed that the response of wheat yield was more sensitive than rice, and no signiifcant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P (TP) and Olsen-P showed soil TP pool was enlarged signiifcantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg–1, respectively. The smaler critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to acti-vate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K.

  14. Long term effects of smoking cessation in hospitalized schizophrenia patients.

    Science.gov (United States)

    Miyauchi, Masatoshi; Kishida, Ikuko; Suda, Akira; Shiraishi, Yohko; Fujibayashi, Mami; Taguri, Masataka; Ishii, Chie; Ishii, Norio; Moritani, Toshio; Hirayasu, Yoshio

    2017-03-07

    The prevalence of smoking in patients with schizophrenia is higher than that in the general population and is an important medical issue. Short-term smoking cessation tends to worsen psychiatric symptoms in patients with schizophrenia but decreases sympathetic nervous system activity and improves plasma cholesterol levels in healthy people. Few studies have assessed the long-term effects of smoking cessation in patients with schizophrenia. Subjects were 70 Japanese patients with schizophrenia (38 smokers, 32 non-smokers). We compared the following clinical parameters between the two groups at baseline (before smoking cessation) and in each group separately between baseline and at three years after smoking cessation: autonomic nervous system activity, plasma cholesterol levels, body weight, drug therapy, and Global Assessment of Functioning scores. We also compared the mean changes in clinical parameters throughout this study between the groups at both time points. Autonomic nervous system activity was assessed by power spectral analysis of heart rate variability. Parasympathetic nervous system activity and the doses of antiparkinsonian drugs in smokers were significantly higher than those in non-smokers at baseline. Smoking cessation was associated with significantly decreased sympathetic nervous system activity and decreased doses of antipsychotics and antiparkinsonian drugs at three years after smoking cessation. However, there was no significant difference in the mean change in clinical factors scores, except for Global Assessment of Functioning scores, between smokers and non-smokers at three years after smoking cessation. Our results suggest that smoking reduces both autonomic nervous system activity and the effectiveness of drug therapy with antipsychotics and antiparkinsonian drugs in patients with schizophrenia, but that both factors could be ameliorated over the long term by smoking cessation. Taken together with the findings of previous studies, smoking

  15. 长期不同施肥下红壤性水稻土综合肥力评价及其效应%Assessment and effects of integrated soil fertility in red paddy soil under different long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    包耀贤; 黄庆海; 徐明岗; 于寒青

    2013-01-01

    以江西进贤红壤性水稻土长期试验为基础,运用模糊数学及统计学方法进行土壤肥力综合评价及其效应研究,以期达到土壤培肥的目的.结果表明,有机质、速效氮、速效磷、速效钾、物理性粘粒、团聚度和团聚体稳定率为研究区土壤肥力评价最小数据集,由其所得评价结果具有高度代表性和科学性.NPKM的SFI值最大且与其他处理均呈显著差异.NPKM、2NPK、NPK各处理SFI值分别高出对照(CK) 31.3%、13.0%和10.1%.SFI值的时间演变为NPKM处理先增后降,临界年限在第12年,N和CK处理缓降,其它处理缓增.一定范围内,二次曲线较直线更能揭示作物产量与SFI的关系,进一步拟合发现,SFI和作物相对产量间符合“S”型波尔兹曼生长曲线,SFI增至0.60时,相对产量增幅趋零,NPKM处理(SFI=0.688)已属于此;模拟可知,作物产量趋稳时相应施肥年限表现为NPKM (2a) <2NPK (8a) <NPK (9a) <NP (11a) <K、NK (13a)<P(14a)处理.综上,长期平衡施肥(NPKM、2NPK和NPK)明显提高土壤综合肥力,NPKM更为显著,但其现状对作物增产已无效,应减施或不施若干年;长期偏施肥对土壤肥力贡献不力,尤其是长期单施氮反使土壤肥力下降.%Based on the data of long-term fertilization experiment in red paddy soil at Jinxian county, Jiangxi province. Integrated soil fertility was evaluated and its effects were analyzed by fuzzy mathematics and statistics methods. The results showed that organic matter, available N, available P, available K, physical clay, aggregate ratio and aggregate stability were proposed a minimum data set( MDS) for soil fertility assessment and the evaluation results produced by MDS had good representativeness and scientificalness. Among all treatments, SFI for NPKM was maximum and had a significant difference with SFI for other treatments. Compared to the control, the SFI of NPKM, 2NPK and NPK treatments was about 31. 3% , 13. 0% and

  16. Biochemical effects on long-term frozen human costal cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Santin, Stefany P.; Martinho Junior, Antonio C.; Yoshito, Daniele; Soares, Fernando A.N.; Mathor, Monica B., E-mail: mathor@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Currently, the progresses on treatment of musculoskeletal diseases with the evolving of artificial implants and the success of tissue transplantation between genetically different individuals have conducted to an increase in radiosterilization. Regarding to tissue transplantation, it is essential to have sterile tissue and many tissue banks use radiosterilization as an effective method to sterilize these tissues. However, high doses of ionizing radiation and the preservation method may induce structural modifications in the tissues, as degradation of structural scaffold, decreasing its mechanical properties. Particularly, cartilage have been preserved in high concentrations of glycerol or deep-frozen at -70 degree C for storage after radiosterilization. Therefore, it is important to study the modifications induced in cartilage by preservation methods and by radiosterilization to determine the appropriated parameters for high quality of human allografts. Costal cartilages were obtained from cadaveric donors and were frozen at -20 degree C for 2 years long in order to compare with previous studies for fresh, deep-frozen and glycerolised cartilages. The mechanical tests were carried out in a universal testing machine until sample failure. According our results, there is no significant statistical difference between stress at break of fresh, long-term - 20 degree C frozen cartilages and deep-frozen cartilage. This early result suggests, regarding to tensile property, that long-term - 20 degree C frozen cartilages corresponds to glycerolised costal cartilages irradiated with 25 kGy or deep-frozen cartilages irradiated with 25 and 50 kGy. Thus, this long-term frozen cartilages may be used for tissue banks, but more studies about effects of ionizing radiation are necessary. (author)

  17. 长期定位施肥对石灰性紫色水稻土古菌群落结构的影响%Effect of long-term fertilization on archaeal community structure in calcareous purplish paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 张小平; 涂仕华; Kristina Lindstr(o)m

    2011-01-01

    manure (NPKM), without fertilization (CK), mineral nitrogen (N), nitrogen-phosphorus (NP) and nitrogen, and phosphorus and potassium (NPK). Our results showed that long-term fertilization significantly affected soil archaeal community structure; the richness and diversity of archaeal community under NM, NP and NPKM were lower than those under the other fertilization treatments (M,NPM, CK, N, and NPK). Based on the DGGE patterns, two soil DNA samples isolated from the NPK-amended soil were used for RFLP analysis of archaea. Phylogenetic analyses showed that archaea in the calcareous purplish paddy soil was highly diverse, and the sequences were closely related to those archaeal sequences isolated from various soils and water environment. Cluster analysis of the DGGE profiles showed that archaeal communities under the eight fertilization treatments clustered into three groups. In soil from paddies currently under rice cultivation, the archaeal communities in the soil amended with M and NPK grouped into the first cluster, while NP was in the second group, and NPKM, NM, CK, N and NPM were in the third. In the soil with wheat cultivation, NP-treated archaeal communities clustered into a cluster, NPKM and M were in the second cluster, and N, NPK, NM, NPM and CK soil communities comprised the third cluster. The cluster analysis showed that crop type impacts the community structure of soil archaea.

  18. Long-term adverse effects of novel antipsychotics.

    Science.gov (United States)

    Masand, P S; Gupta, S

    2000-11-01

    The introduction of novel antipsychotics for the treatment of patients with serious psychiatric illness has alleviated the burden of managing some of the side effects of conventional agents. However, the novel agents may also cause adverse events. The long-term adverse events of concern include weight gain, diabetes, tardive dyskinesia (TD), and those associated with hyperprolactinemia. Recent studies with the novel agents have prompted clinicians to revisit antipsychotic-induced weight gain. Clinically significant weight gain puts patients at risk for coronary heart disease, hypertension, type II diabetes, dyslipidemia, and some types of cancer. More recently, case reports of glucose abnormalities and diabetes have emerged, indicating that some novel antipsychotics may be associated with altered glucose metabolism or insulin sensitivity. The novel antipsychotics may also have a lower propensity for causing TD than the conventional antipsychotics. Side effects associated with hyperprolactinemia include galactorrhea, gynecomastia, and menstrual and sexual dysfunction. All of these adverse events can cause patients to become non-compliant and may thus predispose them to relapse. In this review, the authors summarize the literature on the long-term side effects of the novel antipsychotics and examine the severity of the problem, with recommendations for management. When selecting treatments, clinicians should consider the side-effect profiles of the various antipsychotic agents.

  19. Long-term effects of ionizing radiation on gene expression in a zebrafish model.

    Directory of Open Access Journals (Sweden)

    Lahcen Jaafar

    Full Text Available Understanding how initial radiation injury translates into long-term effects is an important problem in radiation biology. Here, we define a set of changes in the transcription profile that are associated with the long-term response to radiation exposure. The study was performed in vivo using zebrafish, an established radiobiological model organism. To study the long-term response, 24 hour post-fertilization embryos were exposed to 0.1 Gy (low dose or 1.0 Gy (moderate dose of whole-body gamma radiation and allowed to develop for 16 weeks. Liver mRNA profiles were then analyzed using the Affymetrix microarray platform, with validation by quantitative PCR. As a basis for comparison, 16-week old adults were exposed at the same doses and analyzed after 4 hours. Statistical analysis was performed in a way to minimize the effects of multiple comparisons. The responses to these two treatment regimes differed greatly: 360 probe sets were associated primarily with the long-term response, whereas a different 2062 probe sets were associated primarily with the response when adults of the same age were irradiated 4 hours before exposure. Surprisingly, a ten-fold difference in radiation dose (0.1 versus 1.0 Gy had little effect. Analysis at the gene and pathway level indicated that the long-term response includes the induction of cytokine and inflammatory regulators and transcription and growth factors. The acute response includes the induction of p53 target genes and modulation of the hypoxia-induced transcription factor-C/EBP axis. Results help define genes and pathways affected in the long-term, low and moderate dose radiation response and differentiate them from those affected in an acute response in the same tissue.

  20. Reducing soil phosphorus fertility brings potential long-term environmental gains: A UK analysis

    Science.gov (United States)

    Withers, Paul J. A.; Hodgkinson, Robin A.; Rollett, Alison; Dyer, Chris; Dils, Rachael; Collins, Adrian L.; Bilsborrow, Paul E.; Bailey, Geoff; Sylvester-Bradley, Roger

    2017-05-01

    Soil phosphorus (P) fertility arising from historic P inputs is a major driver of P mobilisation in agricultural runoff and increases the risk of aquatic eutrophication. To determine the environmental benefit of lowering soil P fertility, a meta-analysis of the relationship between soil test P (measured as Olsen-P) and P concentrations in agricultural drainflow and surface runoff in mostly UK soils was undertaken in relation to current eutrophication control targets (30-35 µg P L-1). At agronomic-optimum Olsen P (16-25 mg kg-1), concentrations of soluble reactive P (SRP), total dissolved P (TDP), total P (TP) and sediment-P (SS-P) in runoff were predicted by linear regression analysis to vary between 24 and 183 µg L-1, 38 and 315 µg L-1, 0.2 and 9.6 mg L-1, and 0.31 and 3.2 g kg-1, respectively. Concentrations of SRP and TDP in runoff were much more sensitive to changes in Olsen-P than were TP and SS-P concentrations, which confirms that separate strategies are required for mitigating the mobilisation of dissolved and particulate P forms. As the main driver of eutrophication, SRP concentrations in runoff were reduced on average by 60 µg L-1 (71%) by lowering soil Olsen-P from optimum (25 mg kg-1) to 10 mg kg-1. At Olsen-P concentrations below 12 mg kg-1, dissolved hydrolysable P (largely organic) became the dominant form of soluble P transported. We concluded that maintaining agronomic-optimum Olsen-P could still pose a eutrophication risk, and that a greater research focus on reducing critical soil test P through innovative agro-engineering of soils, crops and fertilisers would give long-term benefits in reducing the endemic eutrophication risk arising from legacy soil P. Soil P testing should become compulsory in priority catchments suffering, or sensitive to, eutrophication to ensure soil P reserves are fully accounted for as part of good fertiliser and manure management.

  1. 长期施肥对砂姜黑土作物产量及土壤物理性质的影响%Effects of Long-Term Fertilization on Crop Yield and Soil Physical Properties in Lime Concretion Black Soil

    Institute of Scientific and Technical Information of China (English)

    王道中; 花可可; 郭志彬

    2015-01-01

    [Objective] Maintaining and improving soil fertility, in order to improve soil productivity, is an important part of the sustainable development of agriculture. The effects of long-term combined applications of chemical fertilizer with cow manure (CM), pig manure (PM), and wheat straw (WS) on crop yields and physical properties were investigated in a lime concretion black soil to explore the mechanism of soil fertility improvement.[Method]The crop yield and soil physical properties in seven treatments composed of chemical fertilizer and combined applications of chemical fertilizer with CM, PM, WS from a long-term experimental field established in 1982 were studied to evaluate the effects of different fertilization treatments on crop yield and soil physical properties of lime concretion black soil in the Mengcheng county of Anhui province.[Result]The wheat and soybean yield of the treatment without fertilization in the long-term continuously decreased, and the average annually decreasing rates were 39.0 kg·hm-2 and 70.9 kg·hm-2, respectively. The yield of wheat and soybean fluctuated at a very low level after 25 years. The wheat yield of the treatments with a single chemical fertilizer or a combined application of chemical fertilizer and organic material showed an increasing trend. The yield of the treatments with a combined application of chemical fertilizer and organic material increased when compared to the treatment that applied a single chemical fertilizer; the average annual yield increase rate was above 5%. The yield-increasing effect of cow manure was better than pig manure, and of pig manure was better than straw. The interannual fluctuation range of wheat and soybean yield was large, the coefficient of variation (CV) of the treatment without fertilization was the highest, while applied fertilizer could decreaseCV.The CV of the treatment with a combined application of chemical fertilizer and organic material was lower than the single chemical fertilizer

  2. Long-term Miscanthus Yields Influenced by Location, Genotype, Row Distance, Fertilization and Harvest Season

    DEFF Research Database (Denmark)

    Ugilt Larsen, Søren; Jørgensen, Uffe; Kjeldsen, Jens Bonderup

    2014-01-01

    in Foulum and on coarse sand in Jyndevad. Effects of genotype, row distance and fertilization were investigated. In both trials, yield development over time was characterized by an increase during the first years, optimum yields after 7–8 years and a decrease to a lower level which remained relatively......, and the genotype Giganteus (Miscanthus × giganteus) did not respond to fertilization at all. The highest mean yield in Foulum for the period 1997–2012 was obtained with the shortest row distance (∼18,000 rather than ∼12,000 plants ha−1) and harvested in late autumn, namely 13.1 and 12.0 Mg ha−1 DM annually...... for Giganteus and Goliath, respectively. In Jyndevad, where only Goliath was studied, the highest yield during 1995–2001 was obtained by short row distance, autumn harvest and annual fertilization with 75 kg ha−1 N, with yield increasing up to 116 % in response to fertilization. A mean yield of 14.4 Mg ha−1 DM...

  3. Long term impact of the endocrine disruptor tributyltin on male fertility following a single acute exposure.

    Science.gov (United States)

    Mitra, Sumonto; Srivastava, Ankit; Khandelwal, Shashi

    2017-10-01

    Declining rate of human fertility is a growing concern, where lifestyle and environmental factors play an important role. We recently demonstrated that tributyltin (TBT), an omnipresent endocrine disruptor, affects testicular cells in vitro. In this study, male Wistar rats were gavaged a single dose of 10, 20, and 30 mg/kg TBT-chloride (TBTC) (to mimic accidental exposure in vivo) and sacrificed on day 3 and day 7, respectively. TBT bioavailability was evaluated by estimating total tin content, and essential metal levels were analyzed along with redox molecules (ROS and GSH/GSSG) to understand the effect on physiological conditions. Blood-testicular barrier (BTB) disruption, levels of associated proteins and activity of proteolytic enzymes were evaluated to understand the effect on BTB. Histological analysis of tissue architecture and effect on protein expression of steroidogenic, stress and apoptotic markers were also evaluated. Widespread TBTC pollution can be an eventual threat to male fertility worldwide. © 2017 Wiley Periodicals, Inc.

  4. Long-term combined chemical and manure fertilizations increase soil organic carbon and total nitrogen in aggregate fractions at three typical cropland soils in China.

    Science.gov (United States)

    He, Y T; Zhang, W J; Xu, M G; Tong, X G; Sun, F X; Wang, J Z; Huang, S M; Zhu, P; He, X H

    2015-11-01

    Soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC) and nitrogen (MBN) are important factors of soil fertility. However, effects of the combined chemical fertilizer and organic manure or straw on these factors and their relationships are less addressed under long-term fertilizations. This study addressed changes in SOC, TN, MBC and MBN at 0-20 cm soil depth under three 17 years (September 1990-September 2007) long-term fertilization croplands along a heat and water gradient in China. Four soil physical fractions (coarse free and fine free particulate organic C, cfPOC and ffPOC; intra-microaggregate POC, iPOC; and mineral associated organic C, MOC) were examined under five fertilizations: unfertilized control, chemical nitrogen (N), phosphorus (P) and potassium (K) (NPK), NPK plus straw (NPKS, hereafter straw return), and NPK plus manure (NPKM and 1.5NPKM, hereafter manure). Compared with Control, manure significantly increased all tested parameters. SOC and TN in fractions distributed as MOC > iPOC > cfPOC > ffPOC with the highest increase in cfPOC (329.3%) and cfPTN (431.1%), and the lowest in MOC (40.8%) and MTN (45.4%) under manure. SOC significantly positively correlated with MBC, cfPOC, ffPOC, iPOC and MOC (R(2) = 0.51-0.84, P fertilization for improving soil fertility while straw return should take into account climate factors in Chinese croplands.

  5. Influence of long-term different fertilization on soil weed seed bank diversity of a paddy soil under rice/rape rotation

    Institute of Scientific and Technical Information of China (English)

    Wei FENG; Genxing PAN; Sheng QIANG; Ruhai LI; Jiguang WEI

    2008-01-01

    A long-term fertilized paddy field under rice/ rape rotation in the Taihu Lake Region was selected to investigate the dynamics of soil weed seed diversity.Four fertilizer treatments were performed,including non-fert-ilizer (NF),chemical fertilizer only (CF),chemical fert-ilizer combined with pig manure (CMF) and chemical fertilizer plus crop stalk (CSF).We recorded the seed numbers and crop yields,estimated the weed seed bank density and identified the kinds of weed seeds in the top-soil (0-15 cm) in the study area using a stereomicroscope.Based on the records,we analyzed the effect of long-term fertilization on soil weed seed bank diversity and the rela-tionship between weed seed diversity and crop yields.Comparing the four treatments,it was found that in the cultivating seasons of both rice and rape,the density of soil weed seed bank was the lowest with the treatment of chemical fertilizer plus crop stalk.Whereas,the total num-ber of species and the weed seed bank diversity was the highest.Furthermore,the crop yields were at maximum and kept constant with this treatment.There was a def-inite correlation between fertilizer treatment and soil weed seed bank diversity and crop yields.It was concluded that balancing the fertilizer management was helpful in main-taining soil weed seed bank diversity,increasing crop yields and alleviating crop yield fluctuation.Therefore,among the four fertilizer treatments,chemical fertilizer plus rice crop stalk treatment was the best one to stimulate the productivity of agricultural ecosystems and simulta-neously protect biodiversity.

  6. 长期不同施肥对南方黄泥田水稻子粒品质性状与土壤肥力因子的影响%Effects of long-term fertilization on rice grain qualities and soil fertility factors in yellow paddy fields of southern China

    Institute of Scientific and Technical Information of China (English)

    王飞; 林诚; 李清华; 何春梅; 李昱; 林新坚

    2011-01-01

    Based on data collected at the 26th year of a long-term fertilization experiment in the yellow paddy in Fujian, we investigated the influences of different long-term fertilization regimes on the characters of rice grain quality and the factors of soil fertility.The results show that compared with the control (No fertilization, CK), total essential amino acid contents of rice grain in the treatments of chemical fertilizer plus cattle manure ( NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK) are significantly increased by 25.6%, 16.1% and 13.1% respectively.Contents of coarse protein and starch are also 1.11 -1.41 and 2.3 -3.9 percentage points higher, respectively, with the most significant effect found in the NPKM treatment.Likewise, the N and P contents of rice grain are significantly higher in the NPKM, NPKS, NPK treatments compared with the CK, particularly with an increase of 26.1% and 31.1% in the NPKM treatment.Moreover, the Ca, Mg and S contents of rice grain in the NPKM treatment are increased as well compared with the CK treatment.The amino acid content of rice grain is significantly and positively correlated to the N, P, Mg and S contents of rice grain, and the starch content of rice grain is significantly and positively correlated to the N, Ca and S contents.Soil organic matter and nutrient availability(particularly K) are increased in the NPKM, NPKS and NPK treatments compared with the CK.Furthermore, the key fertility factors including soil organic matter, available N and available P are significantly and positively correlated with amino acid and starch contents of rice grain, and soil available N and available P are significantly and positively correlated with N content and P content of rice grain, respectively.In conclusion, the NPKM treatment is the best fertilization regime for yellow paddy fields, considering overall effects of fertilization on rice yield, grain quality and soil fertility.%在福建黄泥田

  7. Effects of Long-Term Fertilization on Organic Carbon and Nitrogen Accumulation and Activity in a Paddy Soil in Double Cropping Rice Area in Dongting Lake of China%长期施肥对洞庭湖双季稻区水稻土有机碳、氮积累及其活性的影响

    Institute of Scientific and Technical Information of China (English)

    李文军; 彭保发; 杨奇勇

    2015-01-01

    effect was significant (P0.05) correlated with C/N ratio and clay content. On the whole, the correlation coefficients obtained by MBC and MBN were higher than that of DOC and DON. Long-term fertilization significantly (P<0.05) increased the early and late rice yields, the contents of all organic C and N labile fractions in two soil layers were positively correlated with annual rice yields, and with the deepening of soil, the correlation coefficients generally decreased (P<0.05).[Conclusion] In the double cropping rice region of Dongting Lake, as to the same type of soil organic matter component, the content of labile N fraction in fertilized treatments presented a more obvious increasing effect than that of C fraction. Combined application of chemical fertilizer NPK and organic fertilizer, the activity of TOC and TN in two soil layers was significantly increased compared to the unfertilized control, which was the most effective practice for improving the accumulation of soil TOC and TN at 0-40 cm layers as well as the soil productivity. Soil MBC and MBN were more sensitive to predicting the change of soil quality after long-term different fertilizations.%【目的】土壤有机质及其活性是评价土壤肥力的重要指标,研究洞庭湖区典型双季稻轮作水稻土总有机碳、全氮积累及其活性对长期不同施肥的响应特征,为稻田施肥管理和土壤培肥提供科学依据。【方法】依托国家稻田土壤肥力与施肥效应长期试验平台,以不施肥处理(CK)为对照,研究农户习惯施氮磷钾化肥(CF)、施氮钾化肥(NK)、均衡施氮磷钾化肥(NPK)、低量有机肥与氮磷钾化肥配施(LOM,有机肥氮比例为30%)、高量有机肥与氮磷钾化肥配施(HOM,有机肥氮比例为60%)影响下0—20和20—40 cm土层土壤总有机碳(TOC)、全氮(TN)含量及储量积累效应、有机碳氮活性组分含量及其比例的变化特征。【结果】26

  8. Long-term effects of prenatal progesterone exposure

    DEFF Research Database (Denmark)

    Vedel, Cathrine; Larsen, Helle; Holmskov, Anni

    2016-01-01

    children from 498 pregnancies. PREDICT is a placebo-controlled randomized trial examining progesterone for prevention of preterm delivery in unselected twin pregnancies. Medical histories of the children were reviewed, and neurophysiological development was evaluated by the parent-completed Ages and Stages...... between the groups in number or length of admissions, and we found no overall differences in rates of diagnoses. However, the odds ratio for a diagnosis related to the heart was 1.66 (95%CI 0.80;3.37) in favor of placebo among all children, 2.29 (1.02;5.12) in dichorionic twins, and 8.19 (1......) centile) was decreased in the progesterone group (OR 0.34 (0.14;0.86)). CONCLUSIONS: Second and third trimester exposure to progesterone does not seem to have long-term harmful effects on children, but future studies should focus on cardiac disease in the offspring. CLINICAL TRIAL REGISTRATION: Eudra...

  9. Long-Term Lunar Radiation Degradation Effects on Materials

    Science.gov (United States)

    Rojdev, Kristina; ORourke, Mary Jane; Koontz, Steve; Alred, John; Hill, Charles; Devivar, Rodrigo; Morera-Felix, Shakira; Atwell, William; Nutt, Steve; Sabbann, Leslie

    2010-01-01

    The National Aeronautics and Space Administration (NASA) is focused on developing technologies for extending human presence beyond low Earth orbit. These technologies are to advance the state-of-the-art and provide for longer duration missions outside the protection of Earth's magnetosphere. One technology of great interest for large structures is advanced composite materials, due to their weight and cost savings, enhanced radiation protection for the crew, and potential for performance improvements when compared with existing metals. However, these materials have not been characterized for the interplanetary space environment, and particularly the effects of high energy radiation, which is known to cause damage to polymeric materials. Therefore, a study focusing on a lunar habitation element was undertaken to investigate the integrity of potential structural composite materials after exposure to a long-term lunar radiation environment. An overview of the study results are presented, along with a discussion of recommended future work.

  10. Long term effects of irrigation with petrochemical industry wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, O.; Inam, A.; Samiullah; Siddiqi, R.H. [Aligarh Muslim Univ. (India)

    1996-11-01

    Split plot designed field trials were conducted during 1988-1995 to study the long term effects of petrochemical industry wastewater on six crops and agricultural soils. It was observed that wastewater irrigation resulted in increased seed yield of all the crops selected, viz. wheat, triticale, chickpea, lentil and pigeonpea, except summer moong which showed a decrease in seed yield. Soil receiving the wastewater showed no significant changes in pH, total organic carbon, electrical conductivity, cation exchange capacity, micro- and macro-nutrients and SAR. Thus, it may be concluded that treated refinery wastewater met the irrigational quality requirements as its physico-chemical characteristics were within the permissible limits. The same could be said for the accumulation of heavy metals in the soil as well as in the grains making the latter safe for human consumption. 28 refs., 5 figs., 2 tabs.

  11. Long-term storage effects-up-date

    Science.gov (United States)

    Scott, W. R.

    1977-01-01

    The long-term effects of storing batteries over a period of years prior to their use in a synchronous orbit application are discussed. A previous experiment is discussed where life testing was performed on cells after having stored the battery for a period of three years with the cell shorted and at a temperature on the order of 5-10 C. The test consisted of performing a sequence of 10 simulated eclipse seasons (equivalent in cycling of five years in synchronous orbit). Results of this test indicated very little degradation and change in the physical and chemical conditions of the cell. The program was extended for an additional year (battery was stored for four years) under the same conditions and testing. The results of the four year storage (one exception) indicate that no further change occurred that is significant from the three year test.

  12. Soil fertility increases with plant species diversity in a long-term biodiversity experiment.

    Science.gov (United States)

    Dybzinski, Ray; Fargione, Joseph E; Zak, Donald R; Fornara, Dario; Tilman, David

    2008-11-01

    Most explanations for the positive effect of plant species diversity on productivity have focused on the efficiency of resource use, implicitly assuming that resource supply is constant. To test this assumption, we grew seedlings of Echinacea purpurea in soil collected beneath 10-year-old, experimental plant communities containing one, two, four, eight, or 16 native grassland species. The results of this greenhouse bioassay challenge the assumption of constant resource supply; we found that bioassay seedlings grown in soil collected from experimental communities containing 16 plant species produced 70% more biomass than seedlings grown in soil collected beneath monocultures. This increase was likely attributable to greater soil N availability, which had increased in higher diversity communities over the 10-year-duration of the experiment. In a distinction akin to the selection/complementarity partition commonly made in studies of diversity and productivity, we further determined whether the additive effects of functional groups or the interactive effects of functional groups explained the increase in fertility with diversity. The increase in bioassay seedling biomass with diversity was largely explained by a concomitant increase in N-fixer, C4 grass, forb, and C3 grass biomass with diversity, suggesting that the additive effects of these four functional groups at higher diversity contributed to enhance N availability and retention. Nevertheless, diversity still explained a significant amount of the residual variation in bioassay seedling biomass after functional group biomass was included in a multiple regression, suggesting that interactions also increased fertility in diverse communities. Our results suggest a mechanism, the fertility effect, by which increased plant species diversity may increase community productivity over time by increasing the supply of nutrients via both greater inputs and greater retention.

  13. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

    Directory of Open Access Journals (Sweden)

    Yangquanwei Zhong

    Full Text Available Water shortage and nitrogen (N deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L. was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1 in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2 N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3 comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  14. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

    Science.gov (United States)

    Zhong, Yangquanwei; Shangguan, Zhouping

    2014-01-01

    Water shortage and nitrogen (N) deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L.) was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET) and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season) were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1) in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2) N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3) comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  15. Immunosuppressant Effect of Long Term and Subtherapeutic Chlortetracycline in Broiler

    Institute of Scientific and Technical Information of China (English)

    TONG Jian-ming; ZHANG Ri-jun; SA Ren-na; PAN Shu-yuan; HUANG Yan

    2002-01-01

    Experiments were conducted with 270 Abore Acre male broilers to study the influence of dietary chlortetracycline (CTC) on the bursal, thymus and spleen weight index and T, B cell proliferation and antibody responses of broilers. Results show that 50mg/kg CTC had no significant inhibitory effect on thymus and spleen weight index, and T, B cell proliferation of broilers at 21 days old. 150mg/kg CTC had significant inhibitory effect on bursal, thymus and spleen, and T, B cell proliferation (P<0.05). Dietary CTC had a direct inhibitory effect on lymphocyte proliferation in vitro. 50mg/kg and 150mg/kg CTC had a significant inhibitory effect on the antibody responses to BSA (P<0.01). Results demonstrated that subtherapeutic and long term CTC had significant inhibitory effects on immune organs and antibody response. The immunosuppressant effect became higher when the level of CTC increased. 150mg/kg CTC increased the growth rate of broilers significantly.

  16. Simple models and concepts as tools for the study of sustained soil productivity in long-term experiments. I. New soil organic matter and residual effect of P from fertilizers and farmyard manure in Kabete, Kenya

    NARCIS (Netherlands)

    Janssen, B.H.

    2011-01-01

    The rough outcomes of a long-term experiment in Kenya were (re-)interpreted using simple models to find causes of success or failure with regard to sustained soil productivity. A two- pools model calculated the development of soil organic matter, and a practical equation estimated the residual

  17. Bacterial Community Structure after Long-term Organic and Inorganic Fertilization Reveals Important Associations between Soil Nutrients and Specific Taxa Involved in Nutrient Transformations

    Science.gov (United States)

    Li, Fang; Chen, Lin; Zhang, Jiabao; Yin, Jun; Huang, Shaomin

    2017-01-01

    Fertilization has a large impact on the soil microbial communities, which play pivotal roles in soil biogeochemical cycling and ecological processes. While the effects of changes in nutrient availability due to fertilization on the soil microbial communities have received considerable attention, specific microbial taxa strongly influenced by long-term organic and inorganic fertilization, their potential effects and associations with soil nutrients remain unclear. Here, we use deep 16S amplicon sequencing to investigate bacterial community characteristics in a fluvo-aquic soil treated for 24 years with inorganic fertilizers and organics (manure and straw)-inorganic fertilizers, and uncover potential links between soil nutrient parameters and specific bacterial taxa. Our results showed that combined organic-inorganic fertilization increased soil organic carbon (SOC) and total nitrogen (TN) contents and altered bacterial community composition, while inorganic fertilization had little impact on soil nutrients and bacterial community composition. SOC and TN emerged as the major determinants of community composition. The abundances of specific taxa, especially Arenimonas, Gemmatimonas, and an unclassified member of Xanthomonadaceae, were substantially increased by organic-inorganic amendments rather than inorganic amendments only. A co-occurrence based network analysis demonstrated that SOC and TN had strong positive associations with some taxa (Gemmatimonas and the members of Acidobacteria subgroup 6, Myxococcales, Betaproteobacteria, and Bacteroidetes), and Gemmatimonas, Flavobacterium, and an unclassified member of Verrucomicrobia were identified as the keystone taxa. These specific taxa identified above are implicated in the decomposition of complex organic matters and soil carbon, nitrogen, and phosphorus transformations. The present work strengthens our current understanding of the soil microbial community structure and functions under long-term fertilization

  18. Quantitative and compositional responses of ammonia-oxidizing archaea and bacteria to long-term field fertilization

    Science.gov (United States)

    Xue, Chao; Zhang, Xu; Zhu, Chen; Zhao, Jun; Zhu, Ping; Peng, Chang; Ling, Ning; Shen, Qirong

    2016-06-01

    Archaeal (AOA) and bacterial (AOB) ammonia-oxidizer responses to long-term field fertilization in a Mollisol soil were assessed through pyrosequencing of amoA genes. Long-term fertilization treatments including chemical fertilizer (NPK), NPK plus manure (NPKM), and no fertilization over 23 years altered soil properties resulting in significant shifts in AOA and AOB community composition and abundance. NPK exhibited a strong influence on AOA and AOB composition while the addition of manure neutralized the community change induced by NPK. NPK also led to significant soil acidification and enrichment of Nitrosotalea. Nitrosospira cluster 9 and 3c were the most abundant AOB populations with opposing responses to fertilization treatments. NPKM had the largest abundance of ammonia-oxidizers and highest potential nitrification activity (PNA), suggesting high N loss potential due to a doubling of nutrient input compared to NPK. PNA was strongly correlated to AOA and AOB community composition indicating that both were important in ammonium oxidization in this Mollisol soil. Total N and organic C were the most important factors driving shifts in AOA and AOB community composition. The AOA community was strongly correlated to the activities of all sugar hydrolysis associated soil enzymes and was more responsive to C and N input than AOB.

  19. Transfer of metals in soil-grass ecosystems under long-term N, P, K fertilization in Hesse, Germany

    Science.gov (United States)

    Czarnecki, Sezin; Düring, Rolf-Alexander

    2015-04-01

    With this study focuses on the influence of long-term (14 years) fertilization on metal transition from soil to plants is presented. Accumulation of metals in plants due to long-term fertilization and predicting the bioavailability and transfer of metals in the soil-plant system is of great importance with regard to human health as plants represent the first compartment of the terrestrial food chain. Soil and plant (Lolio-Cynosuretum) samples were taken from a 14 years long-term fertilization field experiment which was carried out in Hesse, Germany. Correlation coefficients, transfer factors, and regression analysis was performed for Cd, Cu, Mn, Pb, and Zn to quantify the relative difference in bioavailability of metals to plants or to identify the capacity of plants to accumulate a given metal. Correlation coefficients between metals in soils and in plants show significant relationships (pCu>Zn>Mn>Pb. Results of stepwise multiple linear regression analysis showed that Corg, CEC and bioavailable metal content are the most important predictors for plant metal uptake.

  20. Crop Yield and Soil Responses to Long-Term Fertilization on a Red Soil in Southern China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui-Min; WANG Bo-Ren; XU Ming-Gang; FAN Ting-Lu

    2009-01-01

    A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M) was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,China.Average grain yields of wheat and corn (1 672 and 5 111 kg ha-1,respectively) for the treatment NPKM were significantly higher than those (405 and 310 kg ha-1) of the unfertilized control and single inorganic fertilizer treatments.Compared with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 35 to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year-1,except for the treatments PK and NPKM.After long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+ and available Cu2+ and Zn2+ contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer only.Compared to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil pH.This improved grain yields of wheat and corn,suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil.

  1. Dynamics of Soil and Grain Micronutrients as Affected by Long-Term Fertilization in an Aquic Inceptisol

    Institute of Scientific and Technical Information of China (English)

    LI Ben-Yin; HUANG Shao-Min; WEI Ming-Bao; H.L.ZHANG; SHEN A-Lin; XU Jian-Ming; RUAN Xin-Ling

    2010-01-01

    Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou,China.The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone.Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition.Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu,Zn,Fe,and Mn.Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg-1.The treatments with organic fertilizer had the highest soil DTPA-extractable Cu,Zn,Fe,and Mn after 19 years of cropping and fertilization,thus demonstrating the important role of organic fertilizer application in improving available micronutrient status.Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application.In addition,Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations.These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents,which was due to high soil available P.

  2. Long-term Nutrient Fertilization Increases CO2 Loss in Arctic Tundra

    Science.gov (United States)

    Graham, L. M.; Natali, S.; Rastetter, E. B.; Shaver, G. R.; Risk, D. A.; Loranty, M. M.; Jastrow, J. D.

    2015-12-01

    As anthropogenic climate change warms the Arctic, organic carbon (C) trapped in permafrost is at an increased risk of being released to the atmosphere as carbon dioxide (CO2). At the same time, higher rates of decomposition may increase nutrient availability and enhance plant growth, leading to an uptake of C that may offset respiratory losses. Arctic tundra ecosystems are highly nitrogen (N) limited, and the indirect effects of warming on nutrient availability will be the most likely outcome of increased temperature on plant productivity. This study aims to understand the effects of nutrient addition on arctic CO2 and H2O exchange in a tundra ecosystem at Toolik Lake Field Station, Alaska. The nutrient addition experiment, which began in 2006, is comprised of 7 fertilization treatments: 0.5, 1, 2, 5, and 10 g m-2 of N as NO3- and NH4+ (1:1) with 0.25, 0.5, 1, 2.5, and 5 g m-2 of phosphorus as PO43-; 5 g m-2 of N as NO3-; 5 g m-2 of N as NH4+, and one control plot. Plot-level CO2 and H2O exchange was measured at 5 light levels 7 times over a four-week period in June and July 2015. We measured ecosystem CO2 and H2O exchange using a rectangular plexiglass chamber (0.49 m2) that was connected to an infrared gas analyzer (LI-840). Other ecosystem variables measured include thaw depth, soil moisture and temperature, and normalized difference vegetation index. After 10 years of nutrient addition, fertilization significantly altered ecosystem C cycling. Soil respiration was greatest in the highest fertilization treatment (2.97 μmol m-2 s-1), increasing linearly with nutrient level at a rate of 0.133 μmol m-2 s-1 per g m-2 of N added (R2=0.914). Net CO2 uptake was greatest under highest fertilization (-2.06 μmol m-2 s-1), decreasing linearly with nutrient addition at a rate of -0.068 μmol m-2 s-1 per g m-2 of N added (R2=0.687). These results suggest that as nutrients become more available under a warmer climate, plant productivity increases may not offset respiratory

  3. Long-term effects of prenatal exposure to perfluoroalkyl substances on female reproduction

    DEFF Research Database (Denmark)

    Kristensen, Susanne Lund; Ramlau-Hansen, Cecilia; Ernst, Erik

    2013-01-01

    Does prenatal exposure to perfluoroalkyl substances (PFASs) have long-term effects on female reproductive function?.......Does prenatal exposure to perfluoroalkyl substances (PFASs) have long-term effects on female reproductive function?....

  4. Long-term effects of poultry litter, alum-treated litter, and ammonium nitrate on aluminium availability in soils

    NARCIS (Netherlands)

    Moore, P.A.; Edwards, D.

    2005-01-01

    Received for publication December 14, 2004. Research has shown that alum [Al2(SO4)3·14H2O] applications to poultry litter can greatly reduce phosphorus (P) runoff, as well as decrease ammonia (NH3) volatilization. However, the long-term effects of fertilizing with alum-treated litter are unknown.

  5. 用分形理论评价长期施肥对土壤理化性质的影响%Effects of Long-term Fertilization on Soil Properties Using Fractal Theory

    Institute of Scientific and Technical Information of China (English)

    刘小粉; 刘春增; 李本银; 王守刚

    2012-01-01

    This study investigated the effects of different fertilization practices on soil physical properties and fractal features of aggregates, and evaluated the effects of fractal features on soil physical properties especially on aggregate stability using an existing fractal model. The results showed that the fractal dimension (D) seemed smaller under treatments applying organic materials than under treatment applying chemical fertilizer alone. The fractal dimension had significantly negative correlation with mean weight diameter (MWD) and geometric mean diameter (GMD) , so it could reflect aggregate size distribution as well as soil structure stability. Besides, higher D often indicated higher clay content,higher soil bulk density,and lower organic matter content,while lower D indicated more macroaggregates,lower soil bulk density,and higher organic matter content. The former often induced less macro-pores and more micro-pores, which were bad for soil water and nutrition availability,and vice versa. It was concluded that integrated application of organic and chemical fertilizers was essential for maintaining high soil quality. Under conditions where there were limited organic fertilizers,it was necessary to return crop residues into the field.%为探讨不同施肥处理对土壤理化性质和团聚体分形特征的影响以及用分形特征评价长期施肥对土壤理化性质尤其是土壤团聚体稳定性的影响,采用1个现存的分形模型作为主要研究手段.结果表明,有机肥—化肥混施分形维数较小,单施化肥则较大.分形维数与团聚体平均质量直径(MWD)、几何平均直径(GMD)呈显著负相关,因此,分形维数能同时反映团聚体粒径分布和土壤结构稳定性.另外,分形维数越高,黏粒含量越高,土壤容重越大,有机质含量越少;反之,分形维数越低,大团聚体和有机质含量越高,土壤容重越小.分形维数高时,易导致大孔隙分布少,微小孔隙分布多,

  6. Influence of long-term mineral fertilization on metal contents and properties of soil samples taken from different locations in Hesse, Germany

    Science.gov (United States)

    Czarnecki, S.; Düring, R.-A.

    2015-01-01

    Essential and non-essential metals occur in soils as a result of weathering, industrial processes, fertilization, and atmospheric deposition. Badly adapted cultivation of agricultural soils (declining pH value, application of unsuitable fertilizers) can enhance the mobility of metals and thereby increase their concentrations in agricultural products. As the enrichment of metals in soils occurs over long time periods, monitoring of the long-term impact of fertilization is necessary to assess metal accumulation in agricultural soils. The main objective of this study was to test the effects of different mineral fertilizer variations on soil properties (pH, Corg, and cation exchange capacity (CEC)) and pseudo-total and mobile metal contents of soils after 14 years of fertilizer application and to determine residual effects of the fertilization 8 years after cessation of fertilizer treatment. Soil samples were taken from a field experiment which was carried out at four different locations (210, 260, 360, and 620 m above sea level) in Hesse, Germany. During the study, a significant decrease in soil pH and an evident increase in soil carbon content and cation exchange capacity with fertilization were determined. The CEC of the soils was closely related to their organic C contents. Moreover, pseudo- and mobile metal (Cd, Cu, Mn, Pb, Zn) contents in the soils increased due to application of 14 years of mineral fertilizer treatments (N, P, NP, and NPK) when compared to control plots. Eight years after termination of the fertilization in the soil samples taken from soil profiles of the fertilized plots (NPK) for monitoring the residual effects of the fertilizer application, a decrease of 82.6, 54.2, 48.5, 74.4, and 56.9% in pseudo-total Cd, Cu, Mn, Pb, and Zn contents, respectively, was determined.

  7. Long-term effects of connective tissue cancer treatment.

    Science.gov (United States)

    Mankin, Henry J; Gunnoe, Jaime; Farid, Yasser; Hornicek, Francis J; Gebhardt, Mark C

    2004-09-01

    In 1999, we began a study to assess the long-term effect of connective tissue cancer treatment on clinical, social, and psychologic aspects of the lives of surviving patients. A specially designed computer program generated an 85-item questionnaire, which was sent to more than 2000 patients with malignant bone and soft tissue neoplasms. Twelve hundred forty-four patients responded. The data were entered into a computer system and were correlated with the clinical information already contained in the system for the individual patients. Although there are many possible uses for these data, we chose to do a study comparing the lifestyle and physical and sociologic problems for 144 patients treated with chemotherapy and surgery for high-grade osteosarcoma against a control population consisting of 61 patients treated surgically for benign giant cell tumors of bone. The data show a remarkable degree of compensation on the part of the patients with the malignant tumors in terms of some problems but some significant differences particularly in physical status and functional limitations.

  8. Masculinization and reproductive effects in western mosquitofish (Gambusia affinis) after long-term exposure to androstenedione.

    Science.gov (United States)

    Hou, Li-Ping; Yang, Yang; Shu, Hu; Ying, Guang-Guo; Zhao, Jian-Liang; Fang, Gui-Zhen; Xin, Li; Shi, Wen-Jun; Yao, Li; Cheng, Xue-Mei

    2017-09-12

    Androstenedione (AED) is a naturally occurring steroid hormone. It is metabolized to potent androgens, which may induce androgenic effects in fish. However, little is known whether and how the androgens interfere with the fish gonadal development and reproduction. This study aimed at demonstrating the effects of long-term AED exposure on reproduction and development in mosquitofish (Gambusia affinis). The growth, development and several morphological endpoints, including the segment number and length of anal fin, histological changes of gonads and liver, were evaluated in mosquitofish during development from fertilized embryo to adulthood (180 days) after exposure of AED at environmentally relevant concentrations. We found that the growth (length, body weight and condition factor) of fish was negatively correlated with AED concentration in females, but not in males. The significant elongation of the ray and increment of segment numbers in the anal fin, were detected in all mosquitofish after exposure. Moreover, AED exposure (0.4gµ/L) caused damages in gonads and reduced the number of pregnant females. These findings indicate that AED has adverse effects on the growth and development of the western mosquitofish after long-term exposure (180d). Long-term exposure (180d) to AED, including environmentally relevant concentration (0.4µg/L and 4µg/L), induced masculinization in female mosquitofish under the experimental conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. LONG TERM 32-YEAR-OLD APPLICATION OF FERTILIZERS FOR THE FERTILITY OF THE ORDINARY BLACK SOIL AND PRODUCTIVITY OF SUGAR BEET

    Directory of Open Access Journals (Sweden)

    Neshchadim N. N.

    2016-03-01

    Full Text Available The article deals with the effectiveness of mineral and organic fertilizers in long-term application (for more than thirty years according to the influence on the fertility of ordinary black soil of the Western Ciscaucasia and productivity of sugar beet. The investigations were carried out in the long-term stationary experiment laid on the experimental stationary section "Severokubanskaya agricultural experimental station" of P.P. Lukyanenko Krasnodar Agricultural Research Institute. The experiment was laid simultaneously in time and space in two ten-course crop rotations and combined grain-grass tilled. In the structure of sown areas sugar beet occupied 10% of crop rotation area and was placed after the winter wheat. During three rotations it was studied: 1- control without fertilizer with natural forming level of mineral nutrition; 2- minimal dose N21P26K16 3- medium dose N43P52K33 ; 4 - N43P52K33, 5- high dose N96P104K68; 6- organo-mineral system¹ N43P52K34 + 12 t/ha of manure; 7- organo-mineral system² N20P24K34 + II-III rotations tillage of straw crop + 6 t/ha of manure; 8- medium dose P52K33; 9- medium dose N43K33; 10- medium dose N43K52. The soil which is used by organo-mineral system with increased and high standards of mineral fertilizers had higher concentration of mineral nitrogen. Long systematic application of fertilizer had more noticeable effect on soil phosphorus regime. The provision of soil by exchange potassium tended to decline from rotation to rotation. If at the completion of the first rotation the content of this battery was at the level 362,0-433,0 mg / kg of soil, in 2010, these values were 356,0-405,0 mg / kg of soil, remaining at the level of increased and high provision characterized to ordinary black-soil. Fertilizers for crop rotation provided almost equal yield increase: in the first rotation - 4,9-16,0 t / ha in the second 5,3- 17,1, the third 6,1-15,5 t / ha. In the moderate favorable for moisture and

  10. Long-term effects of transgenic Bacillus thuringiensis cotton on the ...

    African Journals Online (AJOL)

    Long-term effects of transgenic Bacillus thuringiensis cotton on the non-target ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... had no significant negative impacts on A. gossypii in either the short or long term.

  11. Effects of long-term fertilization on microorganisms in flue-cured tobacco grown soil%长期施肥对植烟土壤微生物的影响

    Institute of Scientific and Technical Information of China (English)

    丁伟; 叶江平; 蒋卫; 霍沁建; 陈晓明; 梁永江; 张长华; 袁玲

    2012-01-01

    利用7年的定位施肥试验,研究了不施肥(CK)、 单施化肥(CF)和有机无机肥配施(MCF)对植烟土壤微生物的影响。平板计数、 微生物碳、 氮含量和磷脂脂肪酸的测定结果均表明,土壤微生物数量以有机无机配施的处理最多,单施化肥次之,不施肥最少。在3种施肥处理的土壤中,分别检测出20(CK)、 27(CF)和31种(MCF)磷脂脂肪酸; 施肥提高了代表细菌(1220碳)和放线菌(10Me17: 0和10Me18: 0)的磷脂脂肪酸; 但是,代表真菌的磷脂脂肪酸18: 1ω9c无显著变化(CF)或显著降低(MCF)。有机无机肥配施处理显著提高了土壤微生物的多样性指数和优势度指数,说明有机无机配施改善了土壤生态环境,微生物种群丰富,优势种群突出。在土壤自生固氮菌、 磷细菌和钾细菌中,分离率最高的是芽孢杆菌属,在26%50%之间变化。有机无机肥配施还提高了这3种有益微生物的数量,单施化肥则无显著影响。此外,在有机无机肥配施的土壤中,自生固氮菌、 磷细菌和钾细菌的多样性指数、 均匀度指数和优势度指数均较高。从土壤微生物的角度看,生产上采用有机无机肥配施很有必要。%A 7-year experiment was carried out to investigate the effects of no fertilizer (CK), chemical fertilizer (CF) and the mixture of manure and chemical fertilizer (MCF) on microorganisms in flue-cured tobacco grown soils. Plate count, microbial C and microbial N as well as phosphor lipid fatty acids (PLFAs) showed highest microorganisms in the soil treated with MCF, less with CF and lowest with CK. There were 20 (CK), 27 (CF) and 31 types of PLFAs (MCF) in soils, respectively. Fertilization increased the PLFAs contained in bacteria (12–20C) and actinomycetes (10Me 17:0和10Me18:0). There were no obvious changes in fungal PLFAs (18:1ω9c) in

  12. 长期施肥对黑土有机无机复合度及结合态腐殖质的影响%Effect of long-term fertilization on the organo-mineral complexation and the combined forms of humus of black soil

    Institute of Scientific and Technical Information of China (English)

    迟凤琴; 蔡姗姗; 匡恩俊; 张久明; 周宝库

    2014-01-01

    Effect on long-term different fertilization on the combined forms of humus and the organo-mineral complexation of black soil were studied on the basis of long-term located experiment. The results showed that the contents of organic carbon in soil and heavy fraction and the quantity of organo-mineral complexation were increase with varying degrees under different treatments of long-term fertilization, the degree of organo-mineral complex was decrease in the same way. The contents of the loosely combined humus was richest, the contents of the stsbly combined humus was moderate, the contents of the tightly combined humus was the smallest in all fertilizer treatments. The content of the loosely combined humus, the stsbly combined humus and the ratio of loosely to tightly combined humus tended to increase and the content of loosely combined humus and ratio of loosely to stably combined humus tended to decrease under the fertilizer treatments. The fertility of soil under the chemical fertilizer treatment tended to increase in 0-20 cm layer and tended to decrease in 20-40 cm layer. The organic manure and chemical fertilizers treament improved of soil in the greatest extent, made the humus most active, the influence is stability in the two layers. The effects of the organo-mineral complexation under fertilization in 0-20 cm layer was greater than 20-40 cm layer and the effects of combined forms of humus under fertilization in 20-40 cm layer was greater than 0-20 cm layer.%以黑土长期定位试验为基础,研究长期不同施肥对黑土腐殖质结合形态及有机无机复合度影响。结果表明,长期不同施肥均可不同程度提高土壤的有机碳、重组有机碳、原土复合量,降低原土复合度。三种施肥处理的土壤结合态腐殖质以松结态为主,紧结态其次,稳结态最少。施肥提升土壤的松结态及稳结态腐殖质含量、土壤松/紧比值;降低紧结态腐殖质含量及土壤松/稳比值。

  13. New strategies for submicron characterization the carbon binding of reactive minerals in long-term contrasting fertilized soils: implications for soil carbon storage

    Science.gov (United States)

    Xiao, Jian; He, Xinhua; Hao, Jialong; Zhou, Ying; Zheng, Lirong; Ran, Wei; Shen, Qirong; Yu, Guanghui

    2016-06-01

    Mineral binding is a major mechanism for soil carbon (C) stabilization. However, the submicron information about the in situ mechanisms of different fertilization practices affecting organo-mineral complexes and associated C preservation remains unclear. Here, we applied nano-scale secondary ion mass spectrometry (NanoSIMS), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure spectroscopy (XAFS) to examine differentiating effects of inorganic versus organic fertilization on interactions between highly reactive minerals and soil C preservation. To examine such interactions, soils and their extracted colloids were collected during a 24-year long-term fertilization period (1990-2014) (no fertilization, control; chemical nitrogen (N), phosphorus (P), and potassium (K) fertilization, NPK; and NPK plus swine manure fertilization, NPKM). The results for different fertilization conditions showed a ranked soil organic matter concentration with NPKM > NPK > control. Meanwhile, oxalate-extracted Al (Alo), Fe (Feo), short-range ordered Al (Alxps), Fe (Fexps), and dissolved organic carbon (DOC) ranked with NPKM > control > NPK, but the ratios of DOC / Alxps and DOC / Fexps ranked with NPKM > NPK > control. Compared with the NPK treatment, the NPKM treatment enhanced the C-binding loadings of Al and Fe minerals in soil colloids at the submicron scale. Furthermore, a greater concentration of highly reactive Al and Fe minerals was presented under NPKM than under NPK. Together, these submicron-scale findings suggest that both the reactive mineral species and their associations with C are differentially affected by 24-year long-term inorganic and organic fertilization.

  14. Effects of Long-Term Immunization with Multiple Antigens.

    Science.gov (United States)

    1980-01-01

    who had volunteered as a subject for production of hyperimmune pertussis globulin . He received one injection with 0.5 ml of tetanus toxoid and eight...OCCASIONALLY ASSOCIATED WITH MULTIPLE IMMUNIZATIONS . . . .. .. .. .. .. .. .. .. 9 Serum Sickness . . . . . . . . .. .. .. .. .. .. .. 9 Autoimmune ...they were selected for inclusion in a prospective study to determine whether long-term risks were associated with human " hyperimmunization ." Results

  15. Long-Term Effects of Neurofeedback Treatment in Autism

    Science.gov (United States)

    Kouijzer, Mirjam E. J.; de Moor, Jan M. H.; Gerrits, Berrie J. L.; Buitelaar, Jan K.; van Schie, Hein T.

    2009-01-01

    Previously we demonstrated significant improvement of executive functions and social behavior in children with autism spectrum disorders (ASD) treated with 40 sessions of EEG neurofeedback in a nonrandomized waiting list control group design. In this paper we extend these findings by reporting the long-term results of neurofeedback treatment in…

  16. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Directory of Open Access Journals (Sweden)

    X. R. Wei

    2010-10-01

    Full Text Available Nitrous oxide (N2O is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, m slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

  17. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Directory of Open Access Journals (Sweden)

    X. R. Wei

    2010-06-01

    Full Text Available Nitrous oxide (N2O is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, M slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

  18. 有机肥和化肥长期施用对土壤活性有机氮组分及酶活性的影响%Long-term effects of mineral versus organic fertilizers on soil labile nitrogen fractions and soil enzyme activities in agricultural soil

    Institute of Scientific and Technical Information of China (English)

    宋震震; 李絮花; 李娟; 林治安; 赵秉强

    2014-01-01

    本文以中国农业科学院山东禹城长期定位施肥试验为平台,研究了长期施用有机肥和化肥26年后对土壤活性氮库不同组分[颗粒有机氮(POM-N)、可溶性有机氮(DON)、微生物量氮(SMBN)及轻组有机氮(LFOM-N)]及土壤酶活性的影响。结果表明,与不施肥相比,长期施肥显著提高了土壤全氮、颗粒有机氮、可溶性有机氮、微生物量氮以及轻组有机氮的含量,长期施有机肥效果好于化肥,施用高量有机肥效果好于施用常量有机肥。常量施用量下,50%有机肥和50%化肥配施处理其土壤全氮和活性有机氮库各组分含量与高量化肥处理的相当。长期施化肥处理土壤全氮及活性有机氮库各组分含量随施肥量的增加而显著增高。 POM-N对土壤全氮的贡献率最高,且明显受施肥方式的影响,LFOM-N对土壤全氮的贡献率不随施肥方式的改变而变化。长期施肥处理土壤脲酶、碱性磷酸酶和蔗糖酶活性显著增加,它们之间及与土壤全氮、速效磷及有机碳含量间呈现显著或极显著相关性,脲酶活性与土壤各活性氮组分间也存在显著或极显著相关性;但长期施肥后土壤过氧化氢酶的活性低于不施肥处理。%In this paper, the effects of long-term application of organic fertilizer and chemical fertilizer on soil labile nitrogen fractions and some kinds of soil enzyme activities ( urease, catalase, alkaline phosphatase and sucrase ) were studied based on a 26-year long-term field experiment in Chinese Academy of Agricultural Sciences Research Station in Yucheng City, Shandong province, China.The results show that, compared with CK, long term fertilization significantly increases soil total nitrogen , particle organic nitrogen ( POM-N ) , dissolved organic nitrogen ( DON ) , microbial biomass nitrogen ( MBN ) and light fraction organic nitrogen ( LFON ) contents . Treatments of applying organic

  19. Changes in Organic Carbon Index of Grey Desert Soil in Northwest China After Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    XU Yong-mei; LIU Hua; WANG Xi-he; XU Ming-gang; ZHANG Wen-ju; JIANG Gui-ying

    2014-01-01

    Soil organic carbon (SOC), soil microbial biomass carbon (SMBC) and SMBC quotient (SMBC/SOC, qSMBC) are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr (1990-2011) long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon (SOC) concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1) nonfertilization (control);2) chemical nitrogen plus phosphate plus potassium (NPK);3) NPK plus animal manure (NPKM);4) double NPKM (hNPKM) and 5) NPK plus straw (NPKS). Results showed that the SMBC and qSMBC were signiifcantly different among returning, jointing, lfowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the lfowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg-1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM>NPKM>NPKS>CK>NPK. But there were no statistically signiifcant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS>NPKM>CK>hNPKM>NPK. These results indicated that NPKS signiifcantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Signiifcant linear relationships were observed between the annual carbon input and SOC (P<0.01) or SMBC (P<0.05), and between the relative grain yield of wheat and the SOC content as well (P<0.05). But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be beneift to increase SOC and improve soil quality than

  20. Multi-configuration electromagnetic induction measurements at long term agricultural test sites in Germany with different fertilizer and irrigation managements

    Science.gov (United States)

    Kaufmann, Manuela Sarah; von Hebel, Christian; Brogi, Cosimo; Baumecker, Michael; Döring, Thomas; Amelung, Wulf; Vereecken, Harry; van der Kruk, Jan

    2017-04-01

    Electromagnetic induction (EMI) data are often being used to investigate large scale soil properties including clay content, soil water content, and salinity changes for a wide range of applications. For agricultural sites, different management practices such as organic/mineral fertilization, tillage, and/or irrigation are important when interpreting the measured apparent electrical conductivity (ECa). Here, we present EMI data recorded at two long term field experiment (LTFE) agricultural test sites in Thyrow near Berlin (Germany), where different long term fertilizer and irrigation management practices were applied. We used two fixed-boom multi-coil EMI instruments that simultaneously measure over nine different depths of investigation (DOI), recording information ranging between the very shallow (0-0.25 m) ploughing zone including the organic matter and the surface soil (A-Horizon) down to the relatively deep (0-2.7 m) subsoil (B-Horizon) or even substratum (C-Horizon). At both test sites, the prevailing sandy to silty sand in the A- and B-Horizon is underlain by a glacial till C-Horizon resulting in generally low ECa values between 0.5 and 5 mS/m. At one test site, a "static nutrient deficiency experiment" is performed since 1937, where organic fertilizer (farm yard manure) and mineral fertilizers (nitrogen-phosphate-potassium (NPK) and liming) are applied at specific grids. Comparing the fertilizer application grid to the measured EMI data, the lowest ECa values coincide to unfertilized grids whereas the ECa values increase with liming, farm yard manure, and NPK. The visually observed correlation between ECa and the liming treatment was possibly due to the increased pH of the soil, because the fertilizer application increases ion contents that increase the soil electrical conductivity. At the second test site, a "Static Irrigation and Fertilizer Experiment" is conducted, where next to the fertilizer treatment (farm yard manure and nitrogen) part of the field

  1. Responses of bacterial and archaeal ammonia oxidizers to soil organic and fertilizer amendments under long-term management

    Energy Technology Data Exchange (ETDEWEB)

    Wessen, E.; Nyberg, K.; Jansson, J.K.; Hallin, S.

    2010-05-01

    Ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) co-exist in soil, but their relative distribution may vary depending on the environmental conditions. Effects of changes in soil organic matter and nutrient content on the AOB and AOA are poorly understood. Our aim was to compare effects of long-term soil organic matter depletion and amendments with labile (straw) and more recalcitrant (peat) organic matter, with and without easily plant-available nitrogen, on the activities, abundances and community structures of AOB and AOA. Soil was sampled from a long-term field site in Sweden that was established in 1956. The potential ammonia oxidation rates, the AOB and AOA amoA gene abundances and the community structures of both groups based on T-RFLP of amoA genes were determined. Straw amendment during 50 years had not altered any of the measured soil parameters, while the addition of peat resulted in a significant increase of soil organic carbon as well as a decrease in pH. Nitrogen fertilization alone resulted in a small decrease in soil pH, organic carbon and total nitrogen, but an increase in primary production. Type and amount of organic matter had an impact on the AOB and AOA community structures and the AOA abundance. Our findings confirmed that AOA are abundant in soil, but showed that under certain conditions the AOB dominate, suggesting niche differentiation between the two groups at the field site. The large differences in potential rates between treatments correlated to the AOA community size, indicating that they were functionally more important in the nitrification process than the AOB. The AOA abundance was positively related to addition of labile organic carbon, which supports the idea that AOA could have alternative growth strategies using organic carbon. The AOB community size varied little in contrast to that of the AOA. This indicates that the bacterial ammonia oxidizers as a group have a greater ecophysiological diversity and

  2. Trends of Yield and Soil Fertility in a Long-Term Wheat-Maize System

    Institute of Scientific and Technical Information of China (English)

    YANG Xue-yun; SUN Ben-hua; ZHANG Shu-lan

    2014-01-01

    The sustainability of the wheat-maize rotation is important to China’s food security. Intensive cropping without recycling crop residues or other organic inputs results in the loss of soil organic matter (SOM) and nutrients, and is assumed to be non-sustainable. We evaluated the effects of nine different treatments on yields, nitrogen use efifciency, P and K balances, and soil fertility in a wheat-maize rotation system (1991-2010) on silt clay loam in Shaanxi, China. The treatments involved the application ofrecommended dose of nitrogen (N), nitrogen and phosphorus (NP), nitrogen and potassium (NK), phosphorus and potassium (PK), combined NPK, wheat or maize straw (S) with NPK (SNPK), or dairy manure (M) with NPK (M1NPK and M2NPK), along with an un-treated control treatment (CK). The mean yields of wheat and maize ranged from 992 and 2 235 kg ha-1 under CK to 5962 and 6894 kg ha-1 under M2NPK treatment, respectively. Treatments in which either N or P was omitted (N, NK and PK) gave signiifcantly lower crop yields than those in which both were applied. The crop yields obtained under NP, NPK and SNPK treatments were statistically identical, as were those obtained under SNPK and MNPK. However, M2NPK gave a signiifcant higher wheat yield than NP, and MNPK gave signiifcant higher maize yield than both NP and NPK. Wheat yields increased signiifcantly (by 86 to 155 kg ha-1 yr-1) in treatments where NP was applied, but maize yields did not. In general, the nitrogen use efifciency of wheat was the highest under the NP and NPK treatments; for maize, it was the highest under MNPK treatment. The P balance was highly positive under MNPK treatment, increasing by 136 to 213 kg ha-1 annually. While the K balance was negative in most treatments, ranging from 31 to 217 kg ha-1 yr-1, levels of soil available K remained unchanged or increased over the 20 yr. SOM levels increased signiifcantly in all treatments. Overall, the results indicated that combinations of organic manure and

  3. Long-term organic and inorganic fertilizations enhanced basic soil productivity in a lfuvo-aquic soil

    Institute of Scientific and Technical Information of China (English)

    ZHA Yan; WU Xue-ping; GONG Fu-fei; XU Ming-gang; ZHANG Hui-min; CHEN Li-ming; HUANG Shao-min; CAI Dian-xiong

    2015-01-01

    The improvement of soil productivity depends on a rational input of water and nutrients, optimal ifeld management, and the increase of basic soil productivity (BSP). In this study, BSP is deifned as the productive capacity of a farmland soil with its own physical and chemical properties for a speciifc crop season under local ifeld management. Based on 19-yr data of the long-term agronomic experiments (1989–2008) on a lfuvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer (DSSAT ver. 4.0) crop growth model was used to simulate yields by BSP of winter wheat (Triticum aestiviumL.) and summer maize (Zea maysL.) to examine the relationship between BSP and soil organic carbon (SOC) under long-term fertilization. Five treatments were included: (1) no fertilization (control), (2) nitrogen, phosphorus and potassium fertilizers (NPK), (3) NPK plus manure (NPKM), (4) 1.5 times of NPKM (1.5NPKM), and (5) NPK plus straw (NPKS). After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution per-centage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the lfuvo-aquic soil. There were signiifcant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize (P<0.01), and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha–1 when SOC stock increased 1 t C ha–1. Thus, increased SOC accumulation is a crucial way for increasing BSP in lfuvo-aquic soil.The manure or straw combined application with chemical fertilizers signiifcantly enhanced BSP compared to the application of chemical fertilizers alone.

  4. Mineral vs. organic amendments: microbial community structure, activity and abundance of agriculturally relevant microbes are driven by long-term fertilization strategies

    Directory of Open Access Journals (Sweden)

    Davide Francioli

    2016-09-01

    Full Text Available Soil management is fundamental to all agricultural systems and fertilization practices have contributed substantially to the impressive increases in food production. Despite the pivotal role of soil microorganisms in agro-ecosystems, we still have a limited understanding of the complex response of the soil microbiota to organic and mineral fertilization in the very long-term. Here we report the effects of different fertilization regimes (mineral, organic and combined mineral and organic fertilization, carried out for more than a century, on the structure and activity of the soil microbiome. Organic matter content, nutrient concentrations and microbial biomass carbon were significantly increased by mineral, and even more strongly by organic fertilization. Pyrosequencing revealed significant differences between the structures of bacterial and fungal soil communities associated to each fertilization regime. Organic fertilization increased bacterial diversity, and stimulated microbial groups (Firmicutes, Proteobacteria and Zygomycota that are known to prefer nutrient-rich environments, and that are involved in the degradation of complex organic compounds. In contrast, soils not receiving manure harbored distinct microbial communities enriched in oligotrophic organisms adapted to nutrient-limited environments, as Acidobacteria. The fertilization regime also affected the relative abundances of plant beneficial and detrimental microbial taxa, which may influence productivity and stability of the agroecosystem. As expected, the activity of microbial exoenzymes involved in carbon, nitrogen and phosphorous mineralization were enhanced by both types of fertilization. However, in contrast to comparable studies, the highest chitinase and phosphatase activities were observed in the solely mineral fertilized soil. Interestingly, these two enzymes showed also a particular high biomass-specific activities and a strong negative relation with soil pH. As many soil

  5. Mineral vs. Organic Amendments: Microbial Community Structure, Activity and Abundance of Agriculturally Relevant Microbes Are Driven by Long-Term Fertilization Strategies.

    Science.gov (United States)

    Francioli, Davide; Schulz, Elke; Lentendu, Guillaume; Wubet, Tesfaye; Buscot, François; Reitz, Thomas

    2016-01-01

    Soil management is fundamental to all agricultural systems and fertilization practices have contributed substantially to the impressive increases in food production. Despite the pivotal role of soil microorganisms in agro-ecosystems, we still have a limited understanding of the complex response of the soil microbiota to organic and mineral fertilization in the very long-term. Here, we report the effects of different fertilization regimes (mineral, organic and combined mineral and organic fertilization), carried out for more than a century, on the structure and activity of the soil microbiome. Organic matter content, nutrient concentrations, and microbial biomass carbon were significantly increased by mineral, and even more strongly by organic fertilization. Pyrosequencing revealed significant differences between the structures of bacterial and fungal soil communities associated to each fertilization regime. Organic fertilization increased bacterial diversity, and stimulated microbial groups (Firmicutes, Proteobacteria, and Zygomycota) that are known to prefer nutrient-rich environments, and that are involved in the degradation of complex organic compounds. In contrast, soils not receiving manure harbored distinct microbial communities enriched in oligotrophic organisms adapted to nutrient-limited environments, as Acidobacteria. The fertilization regime also affected the relative abundances of plant beneficial and detrimental microbial taxa, which may influence productivity and stability of the agroecosystem. As expected, the activity of microbial exoenzymes involved in carbon, nitrogen, and phosphorous mineralization were enhanced by both types of fertilization. However, in contrast to comparable studies, the highest chitinase and phosphatase activities were observed in the solely mineral fertilized soil. Interestingly, these two enzymes showed also a particular high biomass-specific activities and a strong negative relation with soil pH. As many soil parameters

  6. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi-chun; WANG Guang-huo

    2005-01-01

    The ecosystem characteristics of soil microorganism and the nutrient uptake of irrigated rice were investigated in a split-block experiment with different fertilization treatments, including control (no fertilizer application), PK, NK, NP, NPK fertilization, in the main block, and conventional rice and hybrid rice comparison, in the sub block. Average data of five treatments in five years indicated that the indigenous N supply (INS) capacity ranged from 32.72 to 93.21 kg/ha; that indigenous P supply (IPS)capacity ranged from 7.42 to 32.25 kg/ha; and that indigenous K supply (IKS) capacity ranged from 16.24 to 140.51 kg/ha, which showed that soil available nutrient pool depletion might occur very fast and that P, K deficiency has become a constraint to increasing yields of consecutive crops grown without fertilizer application. It was found that soil nutrient deficiency and unbalanced fertilization to rice crop had negative effect on the diversity of the microbial community and total microbial biomass in the soil.The long-term fertilizer experiment (LTFE) also showed that balanced application of N, P and K promoted microbial biomass growth and improvement of community composition. Unbalanced fertilization reduced microbial N and increased C/N ratio of the microbial biomass. Compared with inbred rice, hybrid rice behavior is characterized by physiological advantage in nutrient uptake and lower internal K use efficiency.

  7. Effects of Different Long-term Fertilization Models on Culturable Microbial Quantity and Enzyme Activities of Lime Concretion Black Soil%长期不同施肥模式对砂姜黑土可培养微生物数量和酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    张向前; 陈欢; 乔玉强; 曹承富; 杜世州; 李玮; 赵竹

    2016-01-01

    Based on long-term located fertilization experiment (year 1981—) in lime concretion black soil area, we studied the effects of without fertilizer application CK, long-term application of single chemical fertilizer NPK, long-term application of single organic fertilizer M, long-term mixed application of organic and chemical fertilizer MNPK (with the same amount of nitrogen) and HMNPK (with the larger amount of nitrogen) on culturable microbial quantity and enzyme activities in soil, in order to reveal the response mechanism of soil microbial quantity and enzyme activities to different fertilization models, and to provide scientific basis and theoretical help for improving lime concretion black soil fertility and quality. The quantity of bacteria, fungi, actinomycetes and Azotobacter of CK was lower than that of other fertilization treatments, and the quantity of bacteria, actinomycetes and Azotobacter of M was significantly higher than that of NPK at middle of filling stage, while the difference in the quantity of fungi between M and NPK was insignificant. The quantity of bacteria, fungi and actinomycetes of MNPK and HMNPK was higher than that of NPK and M, compared to NPK and M, MNPK increased the quantity of bacteria, fungi and actinomycetes by 47.0%, 21.1%, 32.1% and 23.2%, 11.7%, 20.2%, respectively. The difference in the quantity of bacteria, fungi and actinomycetes between MNPK and HMNPK was insignificant at middle of filling stage, while the quantity of Azotobacter of MNPK was higher than that of HMNPK. The activities of invertase, dehydrogenase, acidic and neutral phosphatase and protease of M were higher than that of NPK at middle of filling stage, and increased by 20.9%, 22.1%, 17.7%, 18.4%, 10.0%, respectively. When compared to long-term application of single chemical fertilizer and organic fertilizer, the treatment of long-term mixed application of organic and chemical fertilizer obviously increased the activities of soil invertase, dehydrogenase

  8. Calcium induces long-term legacy effects in a subalpine ecosystem.

    Directory of Open Access Journals (Sweden)

    Urs Schaffner

    Full Text Available Human activities have transformed a significant proportion of the world's land surface, with profound effects on ecosystem processes. Soil applications of macronutrients such as nitrate, phosphorus, potassium or calcium are routinely used in the management of croplands, grasslands and forests to improve plant health or increase productivity. However, while the effects of continuous fertilization and liming on terrestrial ecosystems are well documented, remarkably little is known about the legacy effect of historical fertilization and liming events in terrestrial ecosystems and of the mechanisms involved. Here, we show that more than 70 years after the last application of lime on a subalpine grassland, all major soil and plant calcium pools were still significantly larger in limed than in unlimed plots, and that the resulting shift in the soil calcium/aluminium ratio continues to affect ecosystem services such as primary production. The difference in the calcium content of the vegetation and the topmost 10 cm of the soil in limed vs. unlimed plots amounts to approximately 19.5 g m(-2, equivalent to 16.3% of the amount that was added to the plots some 70 years ago. In contrast, plots that were treated with nitrogen-phosphorus-potassium fertilizer in the 1930s did not differ from unfertilized plots in any of the soil and vegetation characteristics measured. Our findings suggest that the long-term legacy effect of historical liming is due to long-term storage of added calcium in stable soil pools, rather than a general increase in nutrient availability. Our results demonstrate that single applications of calcium in its carbonated form can profoundly and persistently alter ecosystem processes and services in mountain ecosystems.

  9. Long-term effects of synthetic fibers on concrete pipes

    Science.gov (United States)

    Farrokhi Gozarchi, Sasan

    The studies undertaken by this research were to evaluate the long-term performance and durability of synthetic fiber-reinforced concrete pipes. The target long-term performance is for 9000 hours. Two sets of pipes 8 ft. (2400 mm) long with inside diameters of 24 in. (600 mm) and 36 in. (1200 mm) were manufactured, with a wall thickness of 3 and 4 in., respectively. The pipes were produced based on ASTM C76, for a Class III type with a Wall B. The two set of pipes included RCP's (as control) and SYN-FRCP's. The SYN-FRCP's had several fiber dosages ranging from 6 lb/yd3 (3.5 kg/m 3) to 12 lb/yd3 (7.0 kg/m3) in order to evaluate the long-term performance of synthetic fiber-reinforced concrete pipes. The pipes were pre-cracked until the first visible crack was observed in the three-edge bearing test. As a result, the sustained load simulated, was calculated from the Peak D-load observed; and also the appropriate fiber dosages required for the 24. in (600 mm) and 36 in. (900 mm) pipes were obtained. Three of the 24 in. and three of the 36 in. pipes were installed in 7 ft. (2100 mm) and 8 ft. (2400 mm) wide trenches with 16 ft. (4800 mm) and 18 ft. (5500 mm) of cover respectively. The pipe was initially backfilled with native soil up to 2 ft. (600 mm) and 4 ft. (1200 mm) over the top of the pipe then backfilled again with pea-gravel weighing 100 lb/ft3, to a height of 14ft. to simulate the sustained loading. A type two installation was used during the development of the test setup. Once the long-term test set up was complete, the data was immediately recorded, and vertical deflections were observed from the time-dependent behavior of the pipes. It was observed from results obtained from the three-edge bearing test, that synthetic fibers improve the mechanical properties of concrete pipes, in dry-cast manufacturing. Also, it was observed from the time-dependent deformation, that there was no significant deformation of SYN-FRCP, while the shear capacity was enhanced. Based

  10. Effects of Long-term Different Fertilization Regimes on the Rhizospheric Microbial Community Functional Diversity in Paddy Field%长期施肥对双季稻田根际土壤微生物群落功能多样性的影响

    Institute of Scientific and Technical Information of China (English)

    唐海明; 肖小平; 李微艳; 孙耿; 程凯凯

    2016-01-01

    reflected the main carbon source utilized by rhizosphere microbial community. Our objective was to explore the rhizosphere microbial community functional diversity of a paddy field at early and late rice mature stages under different long-term fertilization regimes in a double cropping rice system. A long-term experiment was established in 1986 in Ningxiang county of Hunan Province, China, and five different fertilizer treatments were applied: (1) no fertilizer input (CK), (2) mineral fertilizer alone (MF), (3) rice residue plus mineral fertilizer (RF), (4) 30% organic matter and 70% mineral fertilizer (OM1), and (5) 60% organic matter and 40% mineral fertilizer (OM2). We analyzed the rhizosphere microbial community functional diversity of the fields with the above five treatments using BIOLOG system. The results showed that both applications of organic manure mixed with chemical fertilizer, and chemical fertilizer alone caused high increase of the AWCD while straw incorporation had less effect on the AWCD, which effect was even lower than in the treatment without fertilizer. It was implied that long-term fertilization regime resulted in the variation of the carbon utilization efficiency of rhizosphere soil microbial communities. In addition, the indices of McIntosh under different fertilization regimes were ordered as follows: OM2>OM1>MF>CK>RF at mature stages of early and late rice. And the indices of Richness, Shannon under different fertilization regimes were ordered as follows: OM2>OM1>RF>CK>MF at mature stages of early and late rice. PCA analysis indicated that there were different carbon-substrate-utilization patterns among different fertilizer treatments. Carbohydrates and Amino acids were the main carbon resources utilized by rhizosphere microbes. There were significant differences in carbon-substrate-utilization patterns among different fertilizer treatments. Therefore, the combined application of chemical fertilizer and recycled organic manure could significantly

  11. Adolescent idiopathic scoliosis: natural history and long term treatment effects

    Directory of Open Access Journals (Sweden)

    Asher Marc A

    2006-03-01

    risks of major surgery, a 6 to 29% chance of requiring re-operation, and the remote possibility of developing a pain management problem. Knowledge of adolescent idiopathic scoliosis natural history and long-term treatment effects is and will always remain somewhat incomplete. However, enough is know to provide patients and parents the information needed to make informed decisions about management options.

  12. Effect of long-term farming strategies on soil microbiota and soil health

    Science.gov (United States)

    Sommermann, Loreen; Babin, Doreen; Sandmann, Martin; Smalla, Kornelia; Schellenberg, Ingo; Grosch, Rita; Geistlinger, Joerg

    2017-04-01

    Increasing food and energy demands have resulted in considerable intensification of farming practices, which brought about severe consequences for agricultural soils, e.g. loss of fertility, erosion and enrichment of soil-borne plant diseases. In order to maintain soil quality and health for the future, the development of more extensive and sustainable farming strategies is urgently needed. The soil microbiome is regarded as a key player in soil ecosystem functions, particularly the natural ability of soils to suppress plant pathogens (suppressiveness). Recent studies showed that soil microbial communities are influenced by agricultural management. To further analyze the effects of farming strategies on soil suppressiveness and plant performance, agricultural soils from three long-term field trials in Thyrow, Bernburg (both in Germany) and Therwil (Switzerland) were sampled and subjected to molecular profiling of soil bacteria and fungi using marker genes and high-throughput amplicon sequencing. Significant effects on bacterial as well as fungal community composition, including plant pathogenic and beneficial taxa, were observed among variants of tillage and crop rotation. The least effect on both communities had fertilization, with no significance between variants. Subsequently, the same soils were subjected to growth chamber pot experiments with lettuce as a model (Lactuca sativa). After a growth period of six weeks significant differences in lettuce shoot and soil microbial biomass were observed among soil samples of the different long-term trials. Furthermore, the lettuce rhizosphere exhibited diverse bacterial community compositions as observed by DGGE (denaturing gradient gel electrophoresis). Using group-specific PCR-DGGE fingerprints, bacterial responders to fertilization, soil management and crop rotation were identified among different taxonomic groups. Currently, bacterial and fungal amplicon sequencing of rhizosphere and bulk soil from these pot

  13. 长期施用氮肥对土壤细菌硝化基因多样性及组成的影响%Effect of Long-Term Application of Nitrogen Fertilizer on the Diversity of Nitrifying Genes (amoA and hao) in Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    陈春兰; 吴敏娜; 魏文学

    2011-01-01

    以中国科学院桃源农业生态试验站水稻长期定位试验为平台(28°55′49.8″N,111°26′25.7″E),运用PCR、克隆文库构建等分子生物学技术研究长期单施氮肥(尿素)对亚硝化基因(amoA和hao)多样性及其群落结构的影响.结果表明,长期单施氮肥使amoA基因多样性降低(Shannon指数减少了11%),而hao基因多样性几乎不受影响,对amoA优势基因型的影响大于对hao基因的影响;长期施用氮肥使amoA和hao基因的菌群组成分别发生了显著性(p=0.02)和极显著性变化(p=0.002).系统发育分析表明amoA基因主要与未经培养的氨氧化细菌基因相似,相似率主要集中在86%~99%,可能主要来自亚硝化螺菌属;而hao基因主要与Silicibacteria、亚硝化螺菌属(Nitrosospira)和甲基球菌属(Methylococcus)相似,相似率在66%~80%,长期施用氮肥使hao基因主要集中在α-Proteobacteria纲且与Silicibacteria有较近的亲缘关系.总体来说,长期单施氮肥使水稻土中亚硝化基因amoA的多样性降低,使amoA与hao的群落组成发生显著变化.%The aim of this study was to determine the effect of long-term ( 16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and

  14. [Change characteristics of rice yield and soil organic matter and nitrogen contents under various long-term fertilization regimes].

    Science.gov (United States)

    Huang, Jing; Gao, Ju-Sheng; Zhang, Yang-Zhu; Qin, Dao-Zhu; Xu, Ming-Gang

    2013-07-01

    A long-term (1982-2010) field experiment was conducted in the Red Soil Experiment Station of Chinese Academy of Agricultural Sciences in Qiyang County of Hunan Province, South-central China to investigate the dynamic changes of rice yield and soil organic matter (OM) and nitrogen contents under different fertilization treatments. The treatments included NPK, NPKM (M: manure), NPM, NKM, PKM, M, and CK. Fertilization increased the soil OM, total N, and alkaline-hydrolysable N contents and the rice yield. In treatment NPKM, the rice yield across the 28 years maintained at the highest level; while in treatment NPK, the yield showed a decreasing trend, being lower than that in other fertilization treatments. In the treatments applied with manure only or in combining with chemical fertilizers, the soil OM content increased rapidly in the first 16 years, and then fluctuated around a constant level (29.42-39.32 g x kg(-1)). In the treatments of chemical fertilization, the soil OM content only had a quicker increase in the first 8 years, and then fluctuated within a relatively stable range. Fertilization with manure increased the soil OM significantly, as compared to fertilization with chemical fertilizers only. The soil total N content in all fertilization treatments showed a rapid increase in the first 8 years, and the increment was the highest in treatment NPKM. The soil alkaline-hydrolysable N content in all fertilization treatments had a slower increase in the first 12 years, with an average annual increment of 0.66-2.25 mg x kg(-1) x a(-1). In 1994-1998, the soil alkaline-hydrolysable N content in fertilization treatments had a quicker increase, with an average annual increment of 6.45-32.45 mg x kg(-1) x a(-1); but after 1998, the soil alkaline-hydrolysable N content had a slight decrease. It was concluded that organic fertilization was the key measure to stably improve the physical and chemical properties and the productivity of red paddy soils by increasing their

  15. Thermal stability responses of soil organic matter to long-term fertilization practices

    OpenAIRE

    J. Leifeld; Franko, U.; Schulz, E

    2006-01-01

    International audience; We used differential scanning calorimetry (DSC) to infer thermal properties of soil organic matter (SOM) in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M) were sampled in 2004. Soil organic carbon contents were highest for M (2.4%), lowest for N (1.7%)...

  16. Mechanisms of soil organic carbon accumulation from long-term fertilization strategies in two soils: Evidence from nuclear magnetic resonance spectroscopy analysis

    Science.gov (United States)

    Long-term fertilization strategies have been proven to significantly influence soil organic carbon (SOC) accumulation, while the underlying mechanism remains unclear. Using two long-term (>20 y) field experiments of a double-cropped maize-wheat rotation on a Calcaric Fluvisol and paddy rice on a Hyd...

  17. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    NARCIS (Netherlands)

    Connolly, Mark P.; Postma, Maarten J.; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Soren

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted r

  18. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    DEFF Research Database (Denmark)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted...

  19. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    NARCIS (Netherlands)

    Connolly, Mark P.; Postma, Maarten J.; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Soren

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted

  20. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    DEFF Research Database (Denmark)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted......) and lifetime gross tax contributions to derive the discounted net tax contribution from assisted-conception singletons. An investment of €11,078 in a mother aged...

  1. Impact of long-term fertilization practice on soil structure evolution

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Vogel, Hans-Jörg

    2014-01-01

    The study characterized soil structure development and evolution in six plots that were amended with varying amounts of animalmanure (AM) and NPK fertilizer over a period of 106 years in a long-termfertilization experiment in Bad Lauchstädt, Germany. Two intact soil cores (10-cm diameter and 8-cm...... tall) and bulk soil samples were extracted froma depth between 5 and 15-cmfromeach plot. Soil properties including texture, organic carbon, soil–water characteristic, air permeability and diffusivity were measured and analyzed along with X-ray computed tomography (CT) data. Long......-termapplications of AMand NPK had a major impact on soil organic carbon content which increased from 0.015 kg kg−1 (unfertilized plot) to 0.024 kg kg−1 (well fertilized plot, 30 T ha−1 2y−1 AM with NPK). Total porosity linearly followed the organic carbon gradient, increasing from 0.36 to 0.43 m3 m−3. The water holding...... capacity of the soil was considerably increased with the increase of AM and NPK applications. Gas diffusivity and air permeability measurements clearly indicated that the level of soil aeration improved with increasing AMand NPK fertilizer amount. The three-dimensional X-ray CT visualizations revealed...

  2. [Dynamics of microbial biomass P and its affecting factors in a long-term fertilized black soil].

    Science.gov (United States)

    Li, Dongpo; Wu, Zhijie; Chen, Lijun; Zhu, Ping; Ren, Jun; Liang, Chenghua; Peng, Chang; Gao, Hongjun

    2004-10-01

    This paper studied the microbial biomass P in a long-term fertilized black soil. The soil was fertilized by farmyard manure (M2, M4) and chemical fertilizer (NPK), and the dynamics of soil microbial biomass P was monitored during crop growth season. The results showed that the microbial biomass P in different treatments was 8.75-47.68 mg x kg(-1) (M4), 3.02-37.16 mg x kg(-1) (M2), 1.59-10.62 mg x kg(-1) (NPK), and 0.76-6.74 mg x kg(-1) (CK). The microbial biomass P in M4 and M2 was the highest at reproductive growth stage, and that in NPK and CK was the highest at early growth stage. The significant difference of soil microbial biomass P induced by different amounts and types of fertilizer application was not varied with the period and stage of plant growth. In all treatments, no significant correlation was found between the dynamics of soil microbial biomass P and the soil biological, physical and chemical properties in plant growth period. Soil microbial biomass P had a very significant positive correlation with soil biological, physical and chemical properties (expect K), and a significant positive correlation with the N, P and K contents of plants and soil water content.

  3. Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Zhu, Ping; Zhou, Wei

    2016-01-01

    Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into four aggregate sizes (>2000 μm, 2000–250 μm, 250–53 μm, and 250 μm aggregates but reduced SOC storage in <250 μm aggregates due to SOC changes in LF and iPOM. PMID:26898121

  4. Long-term effects of flipper bands on penguins

    Science.gov (United States)

    Gauthier-Clerc, M.; Gendner, J.-P.; Ribic, C.A.; Fraser, William R.; Woehler, Eric J.; Descamps, S.; Gilly, C.; Le, Bohec C.; Le, Maho Y.

    2004-01-01

    Changes in seabird populations, and particularly of penguins, offer a unique opportunity for investigating the impact of fisheries and climatic variations on marine resources. Such investigations often require large-scale banding to identify individual birds, but the significance of the data relies on the assumption that no bias is introduced in this type of long-term monitoring. After 5 years of using an automated system of identification of king penguins implanted with electronic tags (100 adult king penguins were implanted with a transponder tag, 50 of which were also flipper banded), we can report that banding results in later arrival at the colony for courtship in some years, lower breeding probability and lower chick production. We also found that the survival rate of unbanded, electronically tagged king penguin chicks after 2-3 years is approximately twice as large as that reported in the literature for banded chicks. ?? 2004 The Royal Society.

  5. Long-term effects of microgravity and possible countermeasures

    Science.gov (United States)

    Wolfe, James W.; Rummel, John D.

    It is well known that long-term exposure to microgravity causes a number of physiological and biochemical changes in humans; among the most significant are: 1) negative calcium balance resulting in the loss of bone; 2) atrophy of antigravity muscles; 3) fluid shifts and decreased plasma volume; and 4) cardiovascular deconditioning that leads to orthostatic intolerance. It is estimated that a mission to Mars may require up to 300 days in a microgravity environment; in the case of an aborted mission, the astronauts may have to remain in reduced gravity for up to three years. Although the Soviet Union has shown that exercise countermeasures appear to be adequate for exposures of up to on year in space, it is questionable whether astronauts could or should have to maintain such regimes for extremely prolonged missions. Therefore, the NASA Life Sciences Division has initiated a program designed to evaluate a number of methods for providing an artificial gravity environment.

  6. Effects of long-term fertilization on weed community characteristics and carbon, nitrogen and phosphorus stoichiometry during winter-spring season in yellow-clay paddy fields of South China%长期施肥对南方黄泥田冬春季杂草群落及其C、N、P化学计量的影响

    Institute of Scientific and Technical Information of China (English)

    林新坚; 王飞; 王长方; 林诚; 李清华; 何春梅; 李昱

    2012-01-01

    As an important agronomic measure, fertilization affects not only crop growth, but also field weeds and community composition. However, the effects of different fertilization on weed community characteristics are still not fully understood. To that end, a long-term experiment was set up in 1983 at Fujian Experimental Observatory Station, a station for the monitoring (via experimental plots) of long-term farmland conservation practices. The station belongs to the Ministry of Agriculture and is located at 119°04'10" E and 26°13'31" N. The soils at the station are the typical yellow-clay paddy soils originating from foot-slope deposited low-hilly red soils of mid-low-yield paddy fields. The influences of different long-term fertilization schemes on the characteristics of field weed communities and carbon (C), nitrogen (N) and phosphorus (P) stoichiometry during winter-spring seasons were investigated. The main aim was to lay the scientific basis for southern paddy soil fertility improvement and weed management and utilization. The results showed that compared with the control (no fertilization, CK), Shannon uniform index (E) was 0.03—0.07 lower in the treatments of chemical fertilizer plus cattle manure (NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK). Margalef abundant index (DMG) also dropped in NPKM and NPKS treatments. Shannon diversity index (H'), a comprehensive indicator, was 0.02-0.16 lower in fertilization treatments. Compared with CK, weed biomass increased by 89.6%~214.7% in all fertilization treatments. Weed N, P and K contents increased as well, and was most significant for NPKM treatment. In terms of accumulated nutrients, the treatments rank of paddy soils was NPKM > NPKS > NPK. Furthermore, weed C/N and C/P ratios dropped in all fer-tilization treatments. Some significant correlations were noted among weed C/N, C/P and N/P ratios and C/N, C/P, N/P ratios of soil and biomass. Different fertilization schemes influenced weed

  7. The long-term fiscal impact of funding cuts to Danish public fertility clinics.

    Science.gov (United States)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Søren

    2011-12-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted reproductive technology will be affected. To reflect the government perspective, the model assessed the average life course of a cohort of assisted-conception singletons taking into consideration age-specific, per-capita government transfers (e.g. education, health care, family allowances, education, pensions) and lifetime gross tax contributions to derive the discounted net tax contribution from assisted-conception singletons. An investment of €11,078 in a mother aged fiscal consequences of the policy change on the government over many generations. The analytical framework discussed here estimates the net tax revenue of a cohort of assisted-conception children and the discounted net tax revenue that these children pay to the Danish government over their lifetime. The analysis illustrates that the government will save more costs than those directly related to public fertility services because fewer children are likely to be born and consequently to require government services (e.g. education, health care, family allowances). However, over time as the assisted-conception cohort matures and enters the work force. the reduced number of assisted-conception children, attributed to the funding cuts, will negatively impact government accounts due to lost tax revenue. The policy analysis described here suggests that the economic impact of the fertility policy change is dependent on the time frame over which the analysis is considered. In the short term, it is possible to save on assisted reproduction treatment costs; however, taking into consideration the life course of the diminished size of the assisted-conception cohort, this will negatively influence government accounts in

  8. Thermal stability of soil organic matter responds to long-term fertilization practices

    Directory of Open Access Journals (Sweden)

    J. Leifeld

    2006-04-01

    Full Text Available We used differential scanning calorimetry (DSC to infer thermal properties of soil organic matter (SOM in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M were sampled in 2004. Soil organic carbon contents were highest for M (2.4%, lowest for N (1.7%, and similar for MN and NM (2.2%. DSC thermograms were characterized by three peaks at around 354, 430, and 520°C, which were assigned to as thermally labile and stable SOM and combustion residues from lignite, respectively. DSC peak temperatures were relatively constant among treatments, but peak heights normalized to the organic C content of the soil were significantly different for labile and stable SOM. Labile C was higher for M>MN=NM=N, and stable C decreased in the order N=NM>MN=M, showing that agricultural depletion of SOM increases the share of thermally stable C. Lignite-derived C was not affected by management, suggesting a homogeneous deposition across treatments.

  9. Thermal stability responses of soil organic matter to long-term fertilization practices

    Directory of Open Access Journals (Sweden)

    J. Leifeld

    2006-01-01

    Full Text Available We used differential scanning calorimetry (DSC to infer thermal properties of soil organic matter (SOM in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M were sampled in 2004. Soil organic carbon contents were highest for M (2.4%, lowest for N (1.7%, and similar for MN and NM (2.2%. Three heat flow peaks at around 354°C, 430°C, and 520°C, which were assigned to as thermally labile and stable SOM and combustion residues from lignite, respectively, characterized DSC thermograms. DSC peak temperatures were relatively constant among treatments, but peak heights normalized to the organic C content of the soil were significantly different for labile and stable SOM. Labile C was higher for M>MN=NM=N, and stable C decreased in the order N=NM>MN=M, showing that agricultural depletion of SOM increases the share of thermally stable C. Lignite-derived C was not affected by management, suggesting a homogeneous deposition across treatments.

  10. Long-term nutrient fertilization and the carbon balance of permanent grassland: any evidence for sustainable intensification?

    Science.gov (United States)

    Fornara, Dario A.; Wasson, Elizabeth-Anne; Christie, Peter; Watson, Catherine J.

    2016-09-01

    Sustainable grassland intensification aims to increase plant yields while maintaining the ability of soil to act as a sink rather than sources of atmospheric CO2. High biomass yields from managed grasslands, however, can be only maintained through long-term nutrient fertilization, which can significantly affect soil carbon (C) storage and cycling. Key questions remain about (1) how long-term inorganic vs. organic fertilization influences soil C stocks, and (2) how soil C gains (or losses) contribute to the long-term C balance of managed grasslands. Using 43 years of data from a permanent grassland experiment, we show that soils not only act as significant C sinks but have not yet reached C saturation. Even unfertilized control soils showed C sequestration rates of 0.35 Mg C ha-1 yr-1 (i.e. 35 g C m-2 yr-1; 0-15 cm depth) between 1970 and 2013. High application rates of liquid manure (i.e. cattle slurry) further increased soil C sequestration to 0.86 Mg C ha-1 yr-1 (i.e. 86 g C m-2 yr-1) and a key cause of this C accrual was greater C inputs from cattle slurry. However, average coefficients of slurry-C retention in soils suggest that 85 % of C added yearly through liquid manure is lost possibly via CO2 fluxes and organic C leaching. Inorganically fertilized soils (i.e. NPK) had the lowest C-gain efficiency (i.e. unit of C gained per unit of N added) and lowest C sequestration (similar to control soils). Soils receiving cattle slurry showed higher C-gain and N-retention efficiencies compared to soils receiving NPK or pig slurry. We estimate that net rates of CO2-sequestration in the top 15 cm of the soil can offset 9-25 % of GHG (greenhouse gas) emissions from intensive management. However, because of multiple GHG sources associated with livestock farming, the net C balance of these grasslands remains positive (9-12 Mg CO2-equivalent ha-1 yr-1), thus contributing to climate change. Further C-gain efficiencies (e.g. reduced enteric fermentation and use of feed

  11. Effect of extreme value loss on long-term correlated time series

    Science.gov (United States)

    Yuan, Naiming; Fu, Zuntao; Li, Huiqun; Mao, Jiangyu

    2012-07-01

    Effects of extreme value loss on long-term correlated time series are analyzed by means of detrended fluctuation analysis (DFA) and power spectral density analysis. Weaker memory can be detected after removing of extreme values for the artificial long-term correlated data, indicating the emergence of extreme events may be closely related to long-term memory. For observational temperature records, similar results are obtained, but not in all stations. For example, in some stations, only extending of scaling range to smaller time scales occurs, which may be due to the asymmetric distribution of values in the record. By comparing our findings with previous works, clustered positions of the extreme events are recognized as an important property in long-term correlated records. Through a simple numerical test, close relations between extreme events and long-term memory are discovered, which is helpful for our understanding of the effects of extreme value loss on long-term correlated records.

  12. The long-term prognosis for live birth in couples initiating fertility treatments

    DEFF Research Database (Denmark)

    Malchau, S S; Henningsen, A A; Loft, A

    2017-01-01

    , across clinics, evaluating live births after insemination, ART and natural conceptions. STUDY DESIGN, SIZE, DURATION: This register-based national cohort study from Denmark includes all women initiating fertility treatments in public and private clinics with homologous gametes in 2007-2010. PARTICIPANTS...... were estimated 2, 3 and 5 years from the first treatment cycle, in all women, including drop-outs. Birthrates were stratified by type of first treatment (ART/IUI), mode of conception (ART/IUI/natural conception) and female age. MAIN RESULTS AND THE ROLE OF CHANCE: Within 5 years, in women aged ... years (N = 3553), 35-39 years (N = 1156) and ≥40 years (N = 451), a total of 64%, 49% and 16% had a live birth due to treatment, respectively. Additionally, in women aged conception, yielding total 5-year birthrates of 80...

  13. Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes.

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Zhu, Ping; Zhou, Wei

    2016-01-01

    Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into four aggregate sizes (>2000 μm, 2000-250 μm, 250-53 μm, and organic matter (iPOM), and mineral-associated organic matter (mSOM). Physical fractionation showed the iPOM fraction of aggregates dominated C storage, averaging 76.87% of SOC storage. Overall, application of N and NPK fertilizers cannot significantly increase the SOC storage but enhanced C in mSOM of aggregates, whereas MNPK fertilizer resulted in the greatest amount of SOC storage (about 5221.5 g C m(2)) because of the enhanced SOC in LF, iPOM and mSOM of each aggregate. The SNPK fertilizer increased SOC storage in >250 μm aggregates but reduced SOC storage in <250 μm aggregates due to SOC changes in LF and iPOM.

  14. 黄绵土长期定位试验中硝态氮剖面分布特征%Effect of Long-term Located Fertilization on NO3--N Accumulation in the Profile of Loessial Soil

    Institute of Scientific and Technical Information of China (English)

    杨孔雀; 郝明德; 臧逸飞; 孙占育; 高亚利

    2011-01-01

    对1982年建立的长期肥料定位试验的土壤剖面硝态氮含量变化进行分析.结果表明,经25 a种植冬小麦施用不同肥料后,土壤0~400 cm土层硝态氮含量差异显著,施N、NP、NPK在200cm出现累积峰,各处理在300 cm以下硝态氮含量显著减少(低于1.0 mg/kg).对于CK、和单施P处理的100 cm以下土壤因长期没有N肥的补给,作物的长期吸收利用,而趋于耗竭(低于1.0 mg/kg);单施N和NP配施处理0~400cm土壤剖面中的氮残留量高达1 323.3kg/hm2,是不施肥的23.3倍,NPK配施也达655.9kg/hm2,是不施肥的11.1倍;M处理的残留量维持在1 018.6~1 753.1 kg/hm2左右,与化肥处理相比残留量显著增加,M处理比CK处理、NM处理比N处理、NPM处理比NP处理和NPKM处理比NPK处理分别增加了93.1%、21.1%、32.5%和83.3%.单施N的硝态氮年残留率最大,相当于施肥量的48.6%;NP配施残留率33.6%,NPK为21.3%.M、NM、NPM和NPKM处理的硝态氮残留率分别为2.6%、33.2%、25.2%和22.8%.平衡施肥能显著减少硝态氮含量,相同施氮水平下,配施磷肥、钾肥、有机肥的硝态氮残留率显著减少.%A 25 years fertilization experiment was carried out with wheat-grown Loessial soil in North China, and the profile of nitric nitrogen content in soil was analyzed. The results showed that there is significant differences on NO3--N contents in the 0-400 cm soil layer, after 25 years cultivation of the winter wheat. It showed an peak accumulation at 200 cm soil layer, and reduced significantly under 300 cm soil layer, ( less than 1.0 mg/kg) in N, NP and NPK treatment. When organic fertilizer supplied only, the accumulation of NO3--N increased in the surface of soil and tended to exhaust under the 120 cm soil layer. The NO3--N content in N and NP treatment was more than 1323.3kg/hm2 ,about 23.3 times of that in CK treatment, and 655.9 kg/hm2 and about 11.1 times in NPK treatment.The NO3 -N in manure treatment was about 1 028.6 to 1 753

  15. Spatial variability of soil total and DTPA-extractable cadmium caused by long-term application of phosphate fertilizers, crop rotation, and soil characteristics.

    Science.gov (United States)

    Jafarnejadi, A R; Sayyad, Gh; Homaee, M; Davamei, A H

    2013-05-01

    Increasing cadmium (Cd) accumulation in agricultural soils is undesirable due to its hazardous influences on human health. Thus, having more information on spatial variability of Cd and factors effective to increase its content on the cultivated soils is very important. Phosphate fertilizers are main contamination source of cadmium (Cd) in cultivated soils. Also, crop rotation is a critical management practice which can alter soil Cd content. This study was conducted to evaluate the effects of long-term consumption of the phosphate fertilizers, crop rotations, and soil characteristics on spatial variability of two soil Cd species (i.e., total and diethylene triamine pentaacetic acid (DTPA) extractable) in agricultural soils. The study was conducted in wheat farms of Khuzestan Province, Iran. Long-term (27-year period (1980 to 2006)) data including the rate and the type of phosphate fertilizers application, the respective area, and the rotation type of different regions were used. Afterwards, soil Cd content (total or DTPA extractable) and its spatial variability in study area (400,000 ha) were determined by sampling from soils of 255 fields. The results showed that the consumption rate of di-ammonium phosphate fertilizer have been varied enormously in the period study. The application rate of phosphorus fertilizers was very high in some subregions with have extensive agricultural activities (more than 95 kg/ha). The average and maximum contents of total Cd in the study region were obtained as 1.47 and 2.19 mg/kg and DTPA-extractable Cd as 0.084 and 0.35 mg/kg, respectively. The spatial variability of Cd indicated that total and DTPA-extractable Cd contents were over 0.8 and 0.1 mg/kg in 95 and 25 % of samples, respectively. The spherical model enjoys the best fitting and lowest error rate to appraise the Cd content. Comparing the phosphate fertilizer consumption rate with spatial variability of the soil cadmium (both total and DTPA extractable) revealed the high

  16. Long-term changes in the chemical composition of soil organic matter, depending on fertilization and crop rotation

    Science.gov (United States)

    Tammik, Kerttu; Kauer, Karin; Astover, Alar

    2017-04-01

    The objective of this study was to determine whether it is possible to assess the impact of different management practices (crop rotation, fertilization (organic and mineral fertilizers) on the chemical composition of soil organic matter, using Fourier transform infrared spectroscopy (FTIR). The study is based IOSDV long-term (established in 1989) three field crop rotation (potato-wheat-barely) experiment located in Tartu, Estonia. Soil samples (Stagnic Albeluvisol) were collected from the 0-20 cm depth in the autumn of 2015, air dried, sieved to 2 mm and grinded to obtain homogeneous samples. The content of soil organic matter was measured by the dry combustion method in a varioMax CNS elemental analyser (ELEMENTAR, Germany). The samples were analysed using Thermo-Nicolet iS10 Fourier Transform Infrared Spectrophotometer (FT-IR) and OMNIC software. An intense and sharp peak was recorded in the region of Si-O vibrations of clay minerals and polysaccharides in all samples analysed. The volume of the peak correlated with the quantity of fertilizers administered

  17. Long-term effects of orthodontic treatment on periodontal health.

    Science.gov (United States)

    Sadowsky, C; BeGole, E A

    1981-08-01

    The periodontal health of a group of ninety-six patients who had received comprehensive fixed-appliance orthodontic treatment during adolescence between 12 and 35 years previously was evaluated. Comparisons were made with a group of 103 adults who were similar with regard to race, sex, age, socioeconomic status, dental awareness, and oral hygiene status but had malocclusions that had not been orthodontically treated. There were no statistically significant differences in the general prevalence of periodontal disease between the two groups. However, more detailed analysis revealed that the orthodontic group had a greater prevalence of mild to moderate periodontal disease in the maxillary posterior and mandibular anterior regions of the mouth, as compared to the control group. The results suggested that orthodontic treatment in adolescence is not a major factor in determining the long-term periodontal health status. No significant amount of either damage or benefit to the periodontal structures could be directly attributed to orthodontic therapy. Conversely, the lack of orthodontic therapy in adolescence does not appear to influence subsequent development or nondevelopment of periodontal disease in adults.

  18. Long-term health effects of unintentional injuries in Danish adults

    DEFF Research Database (Denmark)

    Laursen, Bjarne; Møller, Hanne

    2012-01-01

    and Morbidity Survey in Denmark, 14,566 adults aged 16 years or more were asked about long-term health effects of unintentional injuries. Those reporting long-term health effects were asked about the type and duration of these effects and the accompanying limitation of their daily activities. Information...

  19. Input and Long-Term Effects of Starting Age in Foreign Language Learning

    Science.gov (United States)

    Munoz, Carmen

    2011-01-01

    This study explores the long-term effects of starting age and the effects of input in an instructed language learning setting. First, with respect to the effects of starting age, the findings suggest that in the long term and after similar amounts of input, starting age is not a predictor of language outcomes. Second, the study examines the…

  20. Estimation of PCB content in agricultural soils associated with long-term fertilization with organic waste.

    Science.gov (United States)

    Antolín-Rodríguez, Juan M; Sánchez-Báscones, Mercedes; Martín-Ramos, Pablo; Bravo-Sánchez, Carmen T; Martín-Gil, Jesús

    2016-06-01

    Polychlorinated biphenyl (PCB) pollution related to the use of organic waste as fertilizers in agricultural soils is a cause of major concern. In the study presented herein, PCB concentration was studied through a field trial conducted in two agricultural soils in the province of Palencia (Spain) over a 4-year period, assessing the impact of irrigation and of different types of organic waste materials. The amounts of organic waste added to the soil were calculated according to the nitrogen needs of the crop, and the concentration of PCBs was determined before and after the application of the organic waste. The resulting persistence of the total PCB content in the agricultural soils, compared with the PCB concentration in the original soils, ranged from 27% to 90%, with the lowest value corresponding to irrigated soils treated with municipal solid waste compost (MSWC) and the highest value to non-irrigated soils treated with composted sewage sludge (CSS). An estimate of the PCB content in agricultural soils after the application of organic waste materials until year 2050 was obtained, resulting in a value below 5 ng·g(-1), considered a background value for soils in sites far away from potential pollution sources.

  1. Long-term addition of fertilizer, labile carbon, and fungicide alters the biomass of plant functional groups in a subarctic-alpine community

    DEFF Research Database (Denmark)

    Haugwitz-Hardenberg-Reventlow, M S; Michelsen, A.

    2011-01-01

    , and the aboveground plant biomass was harvested 4 and 16 years after initiating the experiment. In addition, soil inorganic N and P concentration was analyzed the same years. Increased nutrient availability (NPK fertilizer) largely increased the biomass of graminoids and unexpectedly of bryophytes, but not of other......In subarctic ecosystems, plant growth is mostly limited by nutrient availability and harsh climate. Investigating how soil nutrient availability controls the plant community composition may therefore help to understand indirect effects of climate change. The study was conducted in a long-term field...... experiment on a subarctic-alpine fellfield dominated by woody evergreen shrubs, bryophytes, and lichens. To manipulate nutrient availability additions of NPK fertilizer, labile C, and fungicide (benomyl) were done in a fully factorial design, replicated in six blocks. The treatments were run for 10 years...

  2. [Characteristics of soil organic carbon mineralization at different temperatures in paddy soils under long-term fertilization].

    Science.gov (United States)

    Lin, Shan; Chen, Tao; Zhao, Jin-Song; Xiang, Rong-Biao; Hu, Rong-Gui; Zhang, Shui-Qing; Wang, Mi-Lan; Lu, Zhao-Qi

    2014-05-01

    Dynamics of soil organic carbon mineralization affected by long-term fertilizations and temperature in relation to different soil carbon fractions were investigated in paddy soils. Soil samples were collected from the plough layer of 3 long-term national experimental sites in Xinhua, Ningxiang and Taojiang counties of Hunan Province. Mineralization of soil organic C was estimated by 33-day aerobic incubation at different temperatures of 10, 20 and 30 degrees C. The results showed that the rates of CO2 production were higher during the earlier phase (0-13 d) in all treatments, and then decreased according to a logarithm function. Higher incubation temperature strengthened C mineralization in the different treatments. The quantities of cumulative CO2 production in NPK with manure or straw treatments were greater than in inorganic fertilizers treatments. The Q10 values in the different soil treatments ranged from 1.01-1.53. There were significantly positive correlations between the Q10 values and soil total organic carbon (TOC), easy oxidation organic carbon (EOOC), humic acid carbon (C(HA)), fulvic acid carbon (CFA). The cumulative amount of mineralized C was significantly positively correlated with microbial biomass carbon (MBC) at 10 and 20 degrees C, but not significantly at 30 degrees C. Significant correlations were found between the cumulative amount of mineralized C and different soil carbon fractions and C(HA)/C(FA). The correlations of differ- ent soil carbon fractions with the ratio of cumulative mineralized C to TOC were negatively correlated at 10 degrees C, but not significantly at 20 and 30 degrees C. These results suggested that the application of NPK with manure or straw would be helpful to increase the sequestration of C in paddy soils and reduce its contribution of CO2 release in the atmosphere.

  3. Long-Term Application of Bioorganic Fertilizers Improved Soil Biochemical Properties and Microbial Communities of an Apple Orchard Soil.

    Science.gov (United States)

    Wang, Lei; Yang, Fang; E, Yaoyao; Yuan, Jun; Raza, Waseem; Huang, Qiwei; Shen, Qirong

    2016-01-01

    Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF) on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1) control without fertilization (CK); (2) chemical fertilizer application (CF); and (3) bioorganic fertilizer application (BOF). The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009-2015). The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0-20 cm, 20-40 cm, and 40-60 cm), e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas, and Bacillus), Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria, and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter, and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity.

  4. Long-Term Application of Bioorganic Fertilizers Improved Soil Biochemical Properties and Microbial Communities of an Apple Orchard Soil

    Science.gov (United States)

    Wang, Lei; Yang, Fang; E, Yaoyao; Yuan, Jun; Raza, Waseem; Huang, Qiwei; Shen, Qirong

    2016-01-01

    Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF) on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1) control without fertilization (CK); (2) chemical fertilizer application (CF); and (3) bioorganic fertilizer application (BOF). The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009–2015). The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0–20 cm, 20–40 cm, and 40–60 cm), e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas, and Bacillus), Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria, and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter, and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity. PMID:27965631

  5. Long-term application of bioorganic fertilizers improved soil biochemical properties and microbial communities of an apple orchard soil

    Directory of Open Access Journals (Sweden)

    Wang Lei

    2016-11-01

    Full Text Available Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1 control without fertilization (CK; (2 chemical fertilizer application (CF; and (3 bioorganic fertilizer application (BOF. The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009-2015. The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0-20cm, 20-40cm, and 40-60cm, e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas and Bacillus, Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity.

  6. Changes in fertility parameters and contents of heavy metals of soddy-podzolic soils upon the long-term application of sewage sludge

    Science.gov (United States)

    Vasbieva, M. T.; Kosolapova, A. I.

    2015-05-01

    The effect of the long-term sewage sludge (SS) application on the chemical, agrophysical, and biological properties of a soddy-podzolic soil ( Umbric Albeluvisols Abruptic) was studied. Regular SS application in the course of five crop rotations (1976-2013) ensured the improvement of the soil fertility parameters, i.e., a rise in the contents of humus, available phosphorus, and exchangeable potassium; a better state of the soil adsorption complex, bulk density, and aggregation; and higher cellulolytic, nitrification, and urease activities. The efficiencies of SS and the traditional organic fertilizer (cattle manure) were compared. The effect of the long-term application of SS on the accumulation of heavy metals in the soils was also studied. It was found that the application of SS caused a rise in the bulk content of heavy metals and in the contents of their acid-extractable and mobile forms by 1.1-6.0 times. However, the maximum permissible concentrations of heavy metals in the soils were not exceeded. In the soil subjected to the application of SS for more than 25 years, the cadmium concentration somewhat exceeded the maximum permissible concentration.

  7. 长期施用氮磷钾肥和石灰对红壤性水稻土酸性特征的影响%Effect of Long-term Fertilization and Lime Application on Soil Acidity of Reddish Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    鲁艳红; 廖育林; 聂军; 周兴; 谢坚; 杨曾平; 吴浩杰

    2016-01-01

    利用34年的长期定位施肥试验,研究不施肥(CK)、施氮磷钾肥(NPK)和氮磷钾化肥配施石灰(NPK+CaO)对红壤性水稻土不同形态酸、土壤盐基离子及水稻植株阳离子吸收量的影响,探讨土壤交换性H+和Al3+占交换性酸的比例、土壤盐基离子、植株带出阳离子数量与土壤酸度的关系.结果表明,长期NPK处理早、晚稻土壤pH 较CK处理分别降低0.2和0.3个单位,交换性酸提高2.3倍和4.2倍,水解性酸提高35.4%和40.0%;NPK+CaO处理早、晚稻土壤pH较NPK处理分别提高0.5和0.7个单位,较CK处理分别提高0.3和0.4个单位,交换性酸、水解性酸均显著低于NPK和CK处理(p CK> NPK. Exchangeable Al3+ was dominant to exchangeable acidity in acidic soil,and the ratio of exchangeable Al3+ to exchangeable acidity increased with increasing soil acidification. The effects of fertilization,regardless of fertilization mode,on soil CEC,exchangeable Ca2+,Mg2+,exchangeable base ions and base saturation were all very significant. Soil exchangeable base ions were dominated with exchangeable Ca2+,accounting for 81.8%~89.3%. Long-term liming significantly increased the content of soil exchangeable Ca2+. Treatment NPK+CaO was 40.1% and 62.9% higher in soil exchangeable Ca2+ than Treatments CK and NPK,respectively. Exchangeable Ca2+,exchangeable base ions and base saturation were positively related to soil pH,but negatively to exchangeable acidity and hydrolytic acid,and exchangeable Mg2+ was negatively to exchangeable acidity and hydrolytic acid,while exchangeable Na+ was negatively to hydrolytic acidity only. Treatments NPK+CaO and NPK did not vary much,but were both significantly higher than CK(p NPK> CK,in terms of potassium and magnesium uptake and total cation uptake by the crop,the followed an order of NPK> NPK+CaO> CK,and in terms of sodium uptake they followed an order of CK> NPK> NPK+CaO. The removal of Ca,Mg,K and Na and the cations in total with the crops harvested did

  8. Effects of long-term exposure to air pollution on natural-cause mortality

    DEFF Research Database (Denmark)

    Beelen, Rob; Raaschou-Nielsen, Ole; Stafoggia, Massimo

    2013-01-01

    Few studies on long-term exposure to air pollution and mortality have been reported from Europe. Within the multicentre European Study of Cohorts for Air Pollution Effects (ESCAPE), we aimed to investigate the association between natural-cause mortality and long-term exposure to several air...

  9. 长期不同施肥方式对砷在典型壤质潮土及作物中累积的影响%Effects of long-term fertilization on As (arsenate) accumulation in typical fluvo-aquic soils and crops

    Institute of Scientific and Technical Information of China (English)

    王擎运; 张佳宝; 信秀丽; 赵炳梓; 邓西海; 钦绳武

    2012-01-01

    Huang-Huai-Hai Plain is a strategic grain production base in China with a wild distribution of fertile fluvo-aquic soils. During the past 20 years, high-input intensive agriculture with excess chemical fertilizer application has sustained high grain yields. However, unreasonable field management has resulted in potential pollution issues in the plain. In this study, the effects of long-term differential fertilization practices on the accumulation of arsenate (As) in typical fluvo-aquic soils and crops were investigated. Field experiments were launched in 1989, in which 7 treatments were established. The treatments included OM (organic manure), OM+NPK (50% organic manure + 50% chemical fertilizer), NPK, NP, PK, NK and CK (the control experiment with no fertilizer). With over 20 years (1989-2009) of cultivation, As in the surface (0~20 cm) and subsurface (20~40 cm) soil layers markedly accumulated. The soil As content was, however, too low for loading negative effects on eco-agricultural safety. As accumulation in the plain was mainly affected by irrigation and deposition, and relatively less affected by different fertilizer applications. The content of As in phosphorus (P) fertilizers was higher than in nitrogen (N) and potassium (K) fertilizers or in organic manure (OM). Hence P fertilization was the main drive of soil As accumulation in the plain. Nevertheless, long-term P fertilization did not significantly increase soil As content since it was largely used up by crops. Also As accumulation trend slowed with OM fertilization. Crop tissue content of As was in the order of root > stalk > grain. Grain As content was not only significantly lower than that of root or stalk, but also than that of China's national standard. For different fertilization treatments, wheat tissue As content was in the order of PK > OM > OM+NPK > NPK > NP > NK > CK. This was somehow similar to that of soil available P, which was indirectly affected by soil organic matter content. Under OM

  10. 长期施肥对褐土及其微团聚体磷素形态分布和有效性的影响%Effects of Long-term Fertilization on Fractions and Distribution and Availability of Phosphorus in Cinnamon Soil and Its Micro-aggregates

    Institute of Scientific and Technical Information of China (English)

    韩志卿; 韩志才; 张电学; 王秋兵; 吴素霞; 常连生; 谢新宇; 杨会民

    2011-01-01

    通过8年定位试验,研究了长期施肥对褐土及其微团聚体中磷素形态分布和有效性的影响.结果表明,褐土磷素组成以无机磷为主,各级微团聚体各形态磷素含量均随粒级减小而增加,磷素有效性< 10 μm粒级最高,10~50 μm粒级最低.不施肥处理土壤及其微团聚体各形态磷素含量显著减少;施肥均可提高土壤及其微团聚体磷素含量,全磷和无机磷含量以增量NPK化肥处理增加最多,有机磷和有效磷含量则以有机肥(物)料配施化肥处理较高,微团聚体各粒级磷素消耗或积累幅度因施肥制度而异.单施化肥处理土壤及其微团聚体中磷有效性降低,有机肥(物)料配施常量NPK化肥处理积累态磷有效性显著提高.采用有机肥(物)料配施常量NPK化肥是改善土壤磷素肥力的有效措施.%Eight years location experiment was conducted in cinnamon soil in Hebei province to study the effect of long-term fertilization on fractions and distribution and availability of phosphorus in cinnamon soil and its micro-aggregates. The results showed that the composition of phosphorus in cinnamon soil was main inorganic phosphorus. With the sizes of micro-aggregates decreased, the content of every P fractions increased. The effectiveness of phosphorus in < 10 μm micro-aggregates was highest, and in 10 -50 μm micro-aggregates lowest. No fertilization remarkably decreased the content of every P fractions in cinnamon soil and its micro-aggregates. Fertilization increased the content of phosphorus in cinnamon soil and its micro-aggregates. The increase of the content of total phosphorus and inorganic phosphorus with increment NPK fertilizers was most. The content of organic P and available P with application organic manure combined with usual NPK was higher than the other treatments. Range of P consumption and accumulation in every sizes micro-aggregates was different under different fertilizer regimes. The constant NPK

  11. [Distribution and enrichment characteristics of organic carbon and total nitrogen in mollisols under long-term fertilization].

    Science.gov (United States)

    Xu, Xiang-ru; Luo, Kun; Zhou, Bao-ku; Wang, Jing-kuan; Zhang, Wen-ju; Xu, Ming-gang

    2015-07-01

    The characteristics and changes of soil organic carbon (SOC) and total nitrogen (TN) in different size particles of soil under different agricultural practices are the basis for better understanding soil carbon sequestration of mollisols. Based on a 31-year long-term field experiment located at the Heilongjiang Academy of Agricultural Sciences (Harbin) , soil samples under six treatments were separated by size-fractionation method to explore changes and distribution of SOC and TN in coarse sand, fine sand, silt and clay from the top layer (0-20 cm) and subsurface layer (20-40 cm). Results showed that long-term application of manure (M) increased the percentages of SOC and TN in coarse sand and clay size fractions. In the top layer, application of nitrogen, phosphorus and potassium fertilizers combined with manure (NPKM) increased the percentages of SOC and TN in coarse sand by 191.3% and 179.3% compared with the control (CK), whereas M application increased the percentages of SOC and TN in clay by 45% and 47% respectively. For subsurface layers, the increase rates of SOC and TN in corresponding parts were lower than that in top layer. In the surface and subsurface layers, the percentages of SOC storage in silt size fraction accounted for 42%-63% and 48%-54%, TN storage accounted for 34%-59% and 41%-47%, respectively. The enrichment factors of SOC and TN in coarse sand and clay fractions of surface layers increased significantly under the treatments with manure. The SOC and TN enrichment factors were highest in the NPKM, being 2.30 and 1.88, respectively, while that in the clay fraction changed little in the subsurface layer.

  12. Effect of Long-Term Rice Straw Return on Soil Glomalin, Carbon and Nitrogen

    Institute of Scientific and Technical Information of China (English)

    NIE Jun; ZHOU Jian-Min; WANG Huo-Yan; CHEN Xiao-Qin; DU Chang-Wen

    2007-01-01

    A long-term experiment was conducted to investigate how long-term fertilization and rice straw incorporation into soil affect soil glomalin, C and N. The combined application of chemical fertilizer and straw resulted in a significant increase in both soil easily extractable glomalin (EEG) and total glomalin (TG) concentrations, as compared with application of only chemical fertilizer or no fertilizer application. The EEG and TG concentrations of the NPKS (nitrogen, phosphorus, and potassium fertilizer application + rice straw return) plot were 4.68% and 5.67% higher than those of the CK (unfertilized control) plot, and 9.87% and 6.23% higher than those of the NPK (nitrogen, phosphorus, and potassium fertilizer applied annually) plot, respectively. Application of only chemical fertilizer did not cause a statistically significant change of soil glomalin compared with no fertilizer application. The changes of soil organic C (SOC) and total N (TN) contents demonstrated a similar trend to soil glomalin in these plots. The SOC and TN contents of NPKS plot were 15.01% and 9.18% higher than those of the CK plot, and 8.85% and 14.76% higher than those of the NPK plot, respectively. Rice straw return also enhanced the contents of microbial biomass C (MBC) and microbial biomass N (MBN) in the NPKS plot by 7.76% for MBC and 31.42% for MBN compared with the CK plot, and 12.66% for MBC and 15.07% for MBN compared with the NPK plots, respectively. Application of only chemical fertilizer, however, increased MBN concentration, but decreased MBC concentration in soil.

  13. Word Length Effects in Long-Term Memory

    Science.gov (United States)

    Tehan, Gerald; Tolan, Georgina Anne

    2007-01-01

    The word length effect has been a central feature of theorising about immediate memory. The notion that short-term memory traces rapidly decay unless refreshed by rehearsal is based primarily upon the finding that serial recall for short words is better than that for long words. The decay account of the word length effect has come under pressure…

  14. Word Length Effects in Long-Term Memory

    Science.gov (United States)

    Tehan, Gerald; Tolan, Georgina Anne

    2007-01-01

    The word length effect has been a central feature of theorising about immediate memory. The notion that short-term memory traces rapidly decay unless refreshed by rehearsal is based primarily upon the finding that serial recall for short words is better than that for long words. The decay account of the word length effect has come under pressure…

  15. 长期定位施肥对黄土旱塬黑垆土土壤酶活性的影响%Effect of Long-term Fertilization on Soil Enzyme Activities in Dryland Black Humus Soil in the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    王淑英; 樊庭录; 丁宁平; 姜小凤; 张平良; 苏敏

    2011-01-01

    以30年(1979~2008年)肥料长期定位试验为基础,探讨长期定位施肥对黄土旱塬黑垆土土壤酶活性的影响及不同土壤酶间相关性.结果表明:SNP和MNP处理可提高土酶蔗糖酶活性,比不施肥对照分别增加19.98%、19.14%;土壤脲酶活性单施M效果最佳,较对照提高30.72%,MNP和SNP处理优于其它处理;MNP提高碱性磷酸酶活性的效果最好、增幅196.5%,单施M和SNP效果次之;单施N可提高土壤蛋白酶活性,较对照增加28.3%,而施P有抑制黄土旱塬黑垆土蛋白酶活性的作用.脲酶与碱性磷酸酶呈显著正相关,相关系数为0.7241,过氧化氢酶与碱性磷酸酶、脲酶呈显著负相关.综合考虑,长期有机-无机NP肥配施是促进黄土旱塬黑垆土土壤良性循环、提高耕地质量的有效施肥管理措施.%Effects of long-term fertilization on soil enzyme activities in dryland black humus soil in the Loess Plateau was studied based on the long-term fertilization experiment from 1979 to 2008. The results showed that nitrogen and phosphorus with farmer manure (MNP), nitrogen and phosphorus with straw (SNP) could improve the soil invertase activity compared with no fertilizer (control) increased by 19.98%, 19.14%. Farmer manure (M) had a great effect on soil urease activities increased by 30.72% compared to the control, next to MNP and SNP. MNP could increase alkaline phos- phatase activities by 196.5% compared with the control, next to M and SNP. Only application of N could increase soil protease activities by 28.3% compared with control, while P could inhibit soil protease activities in dryland black humus soil in the Loess Plateau. There was a significant positive correlation between soil urease and alkaline phosphatase with correlation coefficient of 0.7241, while there was significantly negative correlation between catalase and alkaline phosphatase, urease. Organic-fertilizer (M and S) with NP was an effective practice for dryland black

  16. [Influences of long-term application of organic and inorganic fertilizers on the composition and abundance of nirS-type denitrifiers in black soil].

    Science.gov (United States)

    Yin, Chang; Fan, Fen-Liang; Li, Zhao-Jun; Song, A-Lin; Zhu, Ping; Peng, Chang; Liang, Yong-Chao

    2012-11-01

    The objectives of this study were to explore the effects of long-term organic and inorganic fertilizations on the composition and abundance of nirS-type denitrifiers in black soil. Soil samples were collected from 4 treatments (i. e. no fertilizer treatment, CK; organic manure treatment, OM; chemical fertilizer treatment (NPK) and combination of organic and chemical fertilizers treatment (MNPK)) in Gongzhuling Long-term Fertilization Experiment Station. Composition and abundance of nirS-type denitrifiers were analyzed with terminal restriction fragment length polymorphism (T-RFLP) and real-time quantitative PCR (Q-PCR), respectively. Denitrification enzyme activity (DEA) and soil properties were also measured. Application of organic fertilizers (OM and MNPK) significantly increased the DEAs of black soil, with the DEAs in OM and MNPK being 5.92 and 6.03 times higher than that in CK treatment, respectively, whereas there was no significant difference between NPK and CK. OM and MNPK treatments increased the abundances of nirS-type denitrifiers by 2.73 and 3.83 times relative to that of CK treatment, respectively. The abundance of nirS-type denitrifiers in NPK treatment was not significantly different from that of CK. The T-RFLP analysis of nirS genes showed significant differences in community composition between organic and inorganic treatments, with the emergence of a 79 bp T-RF, a significant decrease in relative abundance of the 84 bp T-RF and a loss of the 99 bp T-RF in all organic treatments. Phylogenetic analysis indicated that the airS-type denitrifiers in the black soil were mainly composed of alpha, beta and gamma-Proteobacteria. The 79 bp-type denitrifiers inhabiting exclusively in organic treatments (OM and MNPK) were affiliated to Pseudomonadaceae in gamma-Proteobacteria and Burkholderiales in beta-Proteobacteria. The 84 bp-types were related to Burkholderiales and Rhodocyclales. Correlation analysis indicated that pH, concentrations of total nitrogen

  17. Long-Term Effects of Psychological Trauma on Psychosocial Functioning

    Science.gov (United States)

    Bolton, Derek; Hill, Jonathan; O'Ryan, Dominic; Udwin, Orlee; Boyle, Stephanie; Yule, William

    2004-01-01

    Background: Most studies of the effects of trauma on mental health have generally not separately assessed psychosocial functioning, and in those that have key issues have received little attention, such as the relation between the time courses of the two kinds of outcome, and detailed assessment of social functioning in a range of domains. The…

  18. Long-Term Effects of a Nursing Home Education Project

    Science.gov (United States)

    Patterson, Robert D.; Gurian, Bennett S.

    1976-01-01

    A survey was conducted by a mental health center to evaluate the effects of a nursing home education project which attempted 1) to teach mental health professionals and nursing home staff how to set up in-service education programs in nursing homes, and 2) to teach nursing home staff mental health principles. (Author/EJT)

  19. Acute and long-term psychiatric side effects of mefloquine

    DEFF Research Database (Denmark)

    Ringqvist, Asa; Bech, Per; Glenthøj, Birte

    2014-01-01

    psychiatric side effects were retrospectively assessed using the SCL-90-R and questions based on Present State Examination (PSE). Subjects reporting suspected psychotic states were contacted for a personal PSE interview. Electronic records of psychiatric hospitalizations and diagnoses were cross-checked. Long...

  20. 同步辐射软X射线近边吸收谱方法研究长期施肥对黑土有机碳官能团的影响%Effects of Long-Term Fertilization on Organic Carbon Functional Groups in Black Soil as Revealed by Synchrotron Radiation Soft X-Ray Near-Edge Absorption Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    王楠; 王帅; 王青贺; 董培博; 李翠兰; 张晋京; 高强; 赵屹东

    2012-01-01

    以定位20年的黑土肥料试验为平台,利用同步辐射软X射线近边吸收谱(C-1s NEXAFS)方法,研究了长期施用化肥以及化肥配施玉米秸秆对土壤有机碳官能团的影响.结果表明:与不施肥的空白处理(CK)相比,单施化肥(N,NPK)后土壤的芳香C和羧基C含量增加,脂族C和羰基C含量下降,脂族C/芳香C比值降低;与单施化肥处理相比,化肥配施玉米秸秆后芳香C含量下降而脂族C含量增加,脂族C/芳香C比值增加,并随玉米秸秆用量增加表现的更为明显;无论配施玉米秸秆与否,NPK肥混施处理的芳香C、脂族C以及脂族C/芳香C比值均高于单施N肥处理.上述结果说明,单施化肥比不施肥使土壤有机碳官能团中芳香类化合物的相对比例增加,而脂肪烃类化合物的相对比例下降;化肥配施玉米秸秆则比单施化肥增加了脂肪烃类化合物的相对比例,配施高量比低量玉米秸秆的增加趋势更为明显,同时NPK肥混施比单施N肥有利于提高脂肪烃类化合物的相对比例.C-1s NEXAFS方法能够原位表征长期定位施肥条件下土壤有机碳官能团组成的变化.%A 20 years (1984-2004) stationary field experiment was conducted to evaluate the effects of long-term application of chemical fertilizers (N or NPK) alone or in combination with low (0.125 kg o hm~z) or high dose of corn stalk (0. 25 kg · hm‐2) on organic carbon functional groups in black soil using synchrotron radiation soft X-ray near-edge absorption spectroscopy (C-ls NEXAFS). Compared with the control (CK) treatment, the aromatic C and the carboxyl C of soil increased, whereas the aliphatic C, the carbonyl C and the aliphatic C/aromatic C ratio decreased after the application of chemical fertilizer alone. After the application of chemical fertilizations in combined with corn stalk, the aromatic C decreased while the aliphatic C and the aliphatic C/aromatic C ratio increased as compared to N or NPK fertilizer

  1. Long-term toxicological effects of paracetamol in rats

    Directory of Open Access Journals (Sweden)

    S.K. Majeed,

    2013-06-01

    Full Text Available The analgesic and antipyretic properties of paracetamol were first described in 1893, then it has been widely available as a non-prescription drug, with a therapeutic profile that reflects widespread safety and efficacy as well as paracetamol became the most widely used analgesic and antipyretic in children. It is the most frequently used over-the counter medicine in young children and is nearly universally used in infants. The drug is used by millions of children every day. The study was designed to study the toxicological effect of therapeutic dose of paracetamol after oral administration for three months in laboratory rats (Rattus norvegicous on the heart, kidney and liver. Results showed oral administration of the paracetamol for three months in laboratory rats showed that this drug has a severe damaging effect on most of the vital organs in the body like kidney, liver and heart.

  2. Long-term effect of silver powder in vivo.

    Science.gov (United States)

    Aoyagi, Hidekazu; Iwasaki, Shin-ich

    2008-07-01

    The cytotoxicity of silver is a known property of this metal. Interestingly, in the cases of argyria and tattoos, Ag remains in the tissue for a long time without causing harm to the host except pigmentation. To understand these contradictions, pure silver implantation by an original subcutaneous injection method was performed. Two sizes of silver powder particles were implanted subcutaneously: 100 nm (P-silver) and the maximum 45 microm (G-silver). The sulfuration of silver and histopathologic changes were observed for a year. Results were as follows: silver affected the host in the case of P-silver to a greater extent than in G-silver, especially on the 7th day and after 2-4 weeks. Nonetheless, the effect of silver weakened at 12 months after implantation. The presence of P-silver caused various histological reactions, while the decline of silver effect on the host was correlated with an increase in the sulfuration of silver.

  3. Long-term cytotoxic effects of contemporary root canal sealers

    Directory of Open Access Journals (Sweden)

    Emmanuel Joao Nogueira Leal da SILVA

    2013-03-01

    Full Text Available Objectives The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks. Material and Methods Fibroblasts (3T3, 1×105 cells per well were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoREZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MTT assay. Data were analyzed using ANOVA and Tukey's test. Results RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05. All the other tested sealers exhibited severe toxicity initially (week 0. MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode. Conclusions RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.

  4. Long-term renoprotective effects of losartan in diabetic nephropathy

    DEFF Research Database (Denmark)

    Andersen, S.; Tarnow, Lise; Cambien, F.

    2003-01-01

    139/74 mmHg (14/8) in both genotype groups during the study (P treatment with losartan has similar beneficial renoprotective effects on progression of diabetic nephropathy in hypertensive...... of the angiotensin II subtype-1 (AT1) receptor antagonist losartan (100 mg o.d.) on kidney function in II and DD type 1 diabetic patients with diabetic nephropathy. RESEARCH DESIGN AND METHODS: A total of 54 hypertensive type 1 diabetic patients with diabetic nephropathy homozygous for the insertion (n = 26...... type 1 diabetic patients with ACE II and DD genotypes....

  5. Genome-wide effects of long-term divergent selection.

    Directory of Open Access Journals (Sweden)

    Anna M Johansson

    2010-11-01

    Full Text Available To understand the genetic mechanisms leading to phenotypic differentiation, it is important to identify genomic regions under selection. We scanned the genome of two chicken lines from a single trait selection experiment, where 50 generations of selection have resulted in a 9-fold difference in body weight. Analyses of nearly 60,000 SNP markers showed that the effects of selection on the genome are dramatic. The lines were fixed for alternative alleles in more than 50 regions as a result of selection. Another 10 regions displayed strong evidence for ongoing differentiation during the last 10 generations. Many more regions across the genome showed large differences in allele frequency between the lines, indicating that the phenotypic evolution in the lines in 50 generations is the result of an exploitation of standing genetic variation at 100s of loci across the genome.

  6. Effects of zafirlukast on capsular contracture: long-term results.

    Science.gov (United States)

    Mazzocchi, M; Dessy, L A; Alfano, C; Scuderi, N

    2012-01-01

    Capsular contracture is a distressing complication after breast augmentation for both the patient and surgeon. Although capsular contracture is a multifactorial process, one common denominator in the successful treatment of this complication is believed to be the abatement of inflammation. Leukotriene antagonists have recently emerged as effective prophylactic agents in reactive airway diseases. A prospective study was carried out on 60 female patients (120 prostheses implanted) with mild/severe capsular contracture in at least one breast. The hardness of capsular contracture was assessed by means of the mammary compliance method. Patients received zafirlukast (Accolate®) for a 6-month period. Mammary compliance was assessed at the start of the study and thereafter monthly, during drug intake and for one year after drug withdrawal. The results show a significant decrease in breast compliance values in the first 6 months, followed by a significant increase one year after the end of drug intake. Indeed, zafirlukast-treated patients displayed a 6.93 percent reduction in mammary compliance after 1 month, 14.42 percent after 3 months, 22.05 percent after 6 months and 22.52 percent after 7 months (1 month after the withdrawal of the drug). Thereafter, mammary compliance values gradually increased. A 5.47 percent reduction in mammary compliance was observed 1 year after drug withdrawal. The present study suggests that zafirlukast may be effective in reducing breast capsule distortion in patients with long-standing contracture, though reduced capsular contracture values are strictly related to the duration of drug intake.

  7. Long-term effects of aluminium dust inhalation.

    Science.gov (United States)

    Peters, Susan; Reid, Alison; Fritschi, Lin; de Klerk, Nicholas; Musk, A W Bill

    2013-12-01

    During the 1950s and 1960s, aluminium dust inhalation was used as a potential prophylaxis against silicosis in underground miners, including in Australia. We investigated the association between aluminium dust inhalation and cardiovascular, cerebrovascular and Alzheimer's diseases in a cohort of Australian male underground gold miners. We additionally looked at pneumoconiosis mortality to estimate the effect of the aluminium therapy. SMRs and 95% CI were calculated to compare mortality of the cohort members with that of the Western Australian male population (1961-2009). Internal comparisons on duration of aluminium dust inhalation were examined using Cox regression. Aluminium dust inhalation was reported for 647 out of 1894 underground gold miners. During 42 780 person-years of follow-up, 1577 deaths were observed. An indication of increased mortality of Alzheimer's disease among miners ever exposed to aluminium dust was found (SMR=1.38), although it was not statistically significant (95% CI 0.69 to 2.75). Rates for cardiovascular and cerebrovascular death were above population levels, but were similar for subjects with or without a history of aluminium dust inhalation. HRs suggested an increasing risk of cardiovascular disease with duration of aluminium dust inhalation (HR=1.02, 95% CI 1.00 to 1.04, per year of exposure). No difference in the association between duration of work underground and pneumoconiosis was observed between the groups with or without aluminium dust exposure. No protective effect against silicosis was observed from aluminium dust inhalation. Conversely, exposure to aluminium dust may possibly increase the risk of cardiovascular disease and dementia of the Alzheimer's type.

  8. EFFECT OF MOBILITY ON SINR IN LONG TERM EVOLUTION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Jolly Parikh

    2016-03-01

    Full Text Available To meet the ongoing demands for high speed broadband communications, network providers are opting for the next generation of mobile technologies like LTE and LTE-Advanced. Standardized by 3GPP, these technologies aim to meet the requirements of higher data rates, low latency, and wider mobility, in varying environments without affecting the quality of service of a network. With higher mobility, the various network performance parameters like signal to interference to noise ratio, throughput, received signal strength indicator etc. get affected. This paper highlights the effect of mobility on signal to interference to noise ratio (SINR characteristics of an IMT-A system in various test environments like In-house (INH, Urban Micro (UMi, Urban Macro (UMa, Rural Macro (RMa, and Suburban Macro (SMa. Simulations have been carried out to obtain spatial plots and SINR vs CDF plots in various test environments, at different user equipment speeds, emphasizing the effects of user equipment speed on the fast fading channel gainsand SINR of the system. By varying the UE speeds from 0 km/hr to 360 km/hr there was an increase in the minimum SINR value required for acceptable performance in a system. It was observed that for given system parameters, the minimum SINR required in RMa environment increased from -5dB to 1dB, in SMa environment it increased from -6dB to -2dB, and in case of UMa environment it increased from -4dB to 1dB, when the UE speed was increased from 0km/hr to 360km/hr. To address the problem of poor SINR in high mobility systems, 3GPP has introduced the technique of Moving Relays. It is used to improve the SINR and hence the channel quality for UEs moving at high speeds in LTE systems.

  9. Effects of long term exposure to hydrogen fluoride on grapevines

    Energy Technology Data Exchange (ETDEWEB)

    Murray, F.

    1984-01-01

    Grapevines Vitis vinifera L. Shiraz were exposed to hydrogen fluoride in open-top chambers for 189 days at mean atmospheric fluoride concentrations of 0.27, 0.17 or 0.07 ..mu..g HFm/sup -3/. Grapevines growing under ambient conditions outside the chambers were exposed to a mean atmospheric fluoride concentration of 0.08 ..mu..g HFm/sup -3/. The maximum leaf fluoride concentrations associated with these treatments were 62, 27, 9 and 15 ..mu..g Fg/sup -1/, respectively. Foliar necrosis was first observed on grapevines exposed to 0.27 and 0.17 ..mu..g HFm/sup -3/ after 83 and 99 days, respectively. Exposure to fluoride increased the fluoride content of berries and peduncles, and reduced leaf chlorophyll a and total chlorophyll concentration at both mid-season and harvest. Exposure to 0.17 ..mu..g HF m/sup -3/ was associated with higher total acid content of grapes than other treatments. Fluoride had no significant effect on bunch weight, number of bunches, grape yield, grape water or potential alcohol content, leaf chlorophyll b or leaf protein concentration. The high accumulation of fluoride in peduncles, but low fluoride accumulation in berries, suggests that the peduncle acts to block the translocation of fluoride from sites of uptake to the fruit. 42 references, 1 figure, 5 tables.

  10. Long-Term Health Effects of Atom Bomb on Japan Not as Bad as Feared: Study

    Science.gov (United States)

    ... Long-Term Health Effects of Atom Bomb on Japan Not as Bad as Feared: Study Survivors of ... 2011 at a nuclear power plant in Fukushima, Japan, after an earthquake triggered a massive tsunami shows ...

  11. Long-term effects of different rotational grazing schedules on the ...

    African Journals Online (AJOL)

    Long-term effects of different rotational grazing schedules on the productivity and ... were still dominant in 1991, the unpalatable grass Aristida junciformis increased in ... grassveld; grazing management; grazing systems; grazing treatments; ...

  12. 长期施肥对黄泥田土壤微生物群落结构及团聚体组分特征的影响%Effects of long-term fertilization on soil microbial community structure and aggregate composition in yellow clayey paddy field

    Institute of Scientific and Technical Information of China (English)

    李清华; 王飞; 林诚; 何春梅; 李昱; 钟少杰; 林新坚

    2015-01-01

    -years long term field fertilizer experiment in Fujian Province was used for the investigation . There were four treatments, CK ( without fertilizer ), NPK ( fertilizer N, P and K), NPKM ( NPK plus cattle manure) and NPKS ( NPK plus rice straw ).The soil samples were collected in the 0 -20 cm soil layer, phospholipid fatty acid technique and wet screening method were employed to study the microbial community structure and water-stable aggregate composition , respectively .[Results] Compared with CK , the long-term fertilization could increase the types of soil microbial phospholipid fatty acid by 16.67%-38.89% and soil microbial biomass by 26.71%-47.30%, which had significant differences of bacterial , fungi and actinomycetes .The no fertilization could lead to the shortage of actinomycetes , but the fertilization with cattle manure ( NPKM ) could promote the species and amount of soil microbial .The first and second principal components explained 89.80%of the total variance in soil phospholidid fatty acids which extracted six main variables , C17:1w8 ( Gram-negative bacteria), C12:0 (bacteria), cy19:0w8 (Burkholderia), C17:0 (Arthrobacter), C18:1w7 (Pseudomonas), and C10Me17:0 ( Actinobacteria ) .Meanwhile the NPKM and NPKS treatments could increase the ratios of 0.25-2.0 mm water-stable aggregate by 4.74-8.47 percentage points , and the fertilization could increase the contents of C and N in above aggregate by 1.63%-32.58%and 3.82%-13.74%, respectively .The NPKS treatment could promote the formation of water-stable aggregate larger than 0.25 mm.The NPKM treatment could increase the contents of C and N in aggregate with different sizes .There were significantly positive correlations between bacterial , actinomycetes or total microbial biomass and water-stable aggregate of 0.25-2.0 mm size , while there were significantly negative correlations between bacterial , actinomycetes or total microbial biomass and water-stable aggregate less than 0.25 mm.There were

  13. Organic and mineral fertilization, respectively, increase and decrease the development of external mycelium of arbuscular mycorrhizal fungi in a long-term field experiment.

    Science.gov (United States)

    Gryndler, M; Larsen, J; Hrselová, H; Rezácová, V; Gryndlerová, H; Kubát, J

    2006-05-01

    Effects of long-term mineral fertilization and manuring on the biomass of arbuscular mycorrhizal fungi (AMF) were studied in a field experiment. Mineral fertilization reduced the growth of AMF, as estimated using both measurements of hyphal length and the signature fatty acid 16:1omega5, whereas manuring alone increased the growth of AMF. The results of AMF root colonization followed the same pattern as AMF hyphal length in soil samples, but not AMF spore densities, which increased with increasing mineral and organic fertilization. AMF spore counts and concentration of 16:1omega5 in soil did not correlate positively, suggesting that a significant portion of spores found in soil samples was dead. AMF hyphal length was not correlated with whole cell fatty acid (WCFA) 18:2omega6,9 levels, a biomarker of saprotrophic fungi, indicating that visual measurements of the AMF mycelium were not distorted by erroneous involvement of hyphae of saprotrophs. Our observations indicate that the measurement of WCFAs in soil is a useful research tool for providing information in the characterization of soil microflora.

  14. Dynamics of bacterial communities in rice field soils as affected by different long-term fertilization practices.

    Science.gov (United States)

    Ahn, Jae-Hyung; Lee, Shin Ae; Kim, Jeong Myeong; Kim, Myung-Sook; Song, Jaekyeong; Weon, Hang-Yeon

    2016-11-01

    Fertilization and the response of the soil microbial community to the process significantly affect crop yield and the environment. In this study, the seasonal variation in the bacterial communities in rice field soil subjected to different fertilization treatments for more than 50 years was investigated using 16S rRNA sequencing. The simultaneous application of inorganic fertilizers and rice straw compost (CAPK) maintained the species richness of the bacterial communities at levels higher than that in the case of non-fertilization (NF) and application of inorganic fertilizers only (APK) in the initial period of rice growth. The seasonal variation in the bacterial community structure in the NF and APK plots showed cyclic behavior, suggesting that the effect of season was important; however, no such trend was observed in the CAPK plot. In the CAPK plot, the relative abundances of putative copiotrophs such as Bacteroidetes, Firmicutes, and Proteobacteria were higher and those of putative oligotrophs such as Acidobacteria and Plactomycetes were lower than those in the other plots. The relative abundances of organotrophs with respiratory metabolism, such as Actinobacteria, were lower and those of chemoautotrophs that oxidize reduced iron and sulfur compounds were higher in the CAPK plot, suggesting greater carbon storage in this plot. Increased methane emission and nitrogen deficiency, which were inferred from the higher abundances of Methylocystis and Bradyrhizobium in the CAPK plot, may be a negative effect of rice straw application; thus, a solution for these should be considered to increase the use of renewable resources in agricultural lands.

  15. Draft Genome Sequence of Pseudomonas sp. Strain 2-92, a Biological Control Strain Isolated from a Field Plot Under Long-Term Mineral Fertilization.

    Science.gov (United States)

    Adam, Zaky; Tambong, James Tabi; Chen, Qing; Lewis, Christopher T; Lévesque, C André; Xu, Renlin

    2014-01-09

    Pseudomonas sp. strain 2-92, isolated from a Canadian field plot under long-term mineral fertilization, strongly inhibits the growth of Fusarium graminearum, Rhizoctonia solani, and Gaeumannomyces graminis. Here, we report the draft genome sequence of Pseudomonas sp. strain 2-92.

  16. Changes in soil carbon and enzyme activity as a result of different long-term fertilization regimes in a greenhouse field.

    Science.gov (United States)

    Zhang, Lili; Chen, Wei; Burger, Martin; Yang, Lijie; Gong, Ping; Wu, Zhijie

    2015-01-01

    In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C) transformations, soil chemical characteristics, and crop yields were monitored after long-term (20-year) fertilization regimes, including no fertilizer (CK), 300 kg N ha-1 and 600 kg N ha-1 as urea (N1 and N2), 75 Mg ha-1 horse manure compost (M), and M with either 300 or 600 kg N ha-1 urea (MN1 and MN2). Compared with CK, fertilization increased crop yields by 31% (N2) to 69% (MN1). However, compared with CK, inorganic fertilization (especially N2) also caused soil acidification and salinization. In the N2 treatment, soil total organic carbon (TOC) decreased from 14.1±0.27 g kg-1 at the beginning of the long-term experiment in 1988 to 12.6±0.11 g kg-1 (Pbiomass C and N. The fertilization regime of the MN1 treatment was identified as optimal because it produced the highest yields and increased soil quality, ensuring sustainability. The results suggest that inorganic fertilizer alone, especially in high amounts, in greenhouse fields is detrimental to soil quality.

  17. Sexual life and fertility desire in long-term HIV serodiscordant couples in Addis Ababa, Ethiopia: a grounded theory study

    Directory of Open Access Journals (Sweden)

    Hailemariam Tewodros G

    2012-10-01

    Full Text Available Abstract Background Even though remarkable progress has been achieved, HIV/AIDS continues to be a major global health priority. HIV discordant relationship is one of the emerging issues in HIV prevention endeavour. In Ethiopia, very little is known about HIV-serodiscordant couples particularly how they manage their sexual relationship and fertility desire. Therefore, we conduct this study with the aim of exploring the experiences of HIV discordant couples about their sexual life, and fertility desire in the context of long-term relationships in Addis Ababa, Ethiopia. Methods A grounded theory approach was employed using in-depth interviews among 36 informants in ART/PMTCT centers of three public hospitals, a health center and one PLHIV association in Addis Ababa. Theoretical sampling was used to recruit 28 clients who lived in a discordant relationship and eight health care providers as key informants. Data collection and analysis were undertaken simultaneously using a constant comparison. The analysis was facilitated using OpenCode software. Results A grounded theory pertaining to sexual life and desire to have a child among HIV discordant couples emerged as “maintaining the relationship” as a core category. Couples pass through a social process of struggle to maintain their relationship. The causal conditions for couples to enter into the process of struggle to maintain their relationship were collectively categorized as “Entering in-to a transition” (knowing HIV serostatus and this includes mismatch of desire to have a child, controversy on safe sex versus desire to have a child, and undeniable change in sexual desire and practice through time were the features in entering into-transition. Then after the transition, couples engaged in certain actions/strategies that are categorized as “dealing with discordancy” such as entertaining partner’s interest by scarifying once self interest to maintain their relationship. Conclusions

  18. Sexual life and fertility desire in long-term HIV serodiscordant couples in Addis Ababa, Ethiopia: a grounded theory study.

    Science.gov (United States)

    Hailemariam, Tewodros G; Kassie, Getnet M; Sisay, Mitike M

    2012-10-24

    Even though remarkable progress has been achieved, HIV/AIDS continues to be a major global health priority. HIV discordant relationship is one of the emerging issues in HIV prevention endeavour. In Ethiopia, very little is known about HIV-serodiscordant couples particularly how they manage their sexual relationship and fertility desire. Therefore, we conduct this study with the aim of exploring the experiences of HIV discordant couples about their sexual life, and fertility desire in the context of long-term relationships in Addis Ababa, Ethiopia. A grounded theory approach was employed using in-depth interviews among 36 informants in ART/PMTCT centers of three public hospitals, a health center and one PLHIV association in Addis Ababa. Theoretical sampling was used to recruit 28 clients who lived in a discordant relationship and eight health care providers as key informants. Data collection and analysis were undertaken simultaneously using a constant comparison. The analysis was facilitated using OpenCode software. A grounded theory pertaining to sexual life and desire to have a child among HIV discordant couples emerged as "maintaining the relationship" as a core category. Couples pass through a social process of struggle to maintain their relationship. The causal conditions for couples to enter into the process of struggle to maintain their relationship were collectively categorized as "Entering in-to a transition" (knowing HIV serostatus) and this includes mismatch of desire to have a child, controversy on safe sex versus desire to have a child, and undeniable change in sexual desire and practice through time were the features in entering into-transition. Then after the transition, couples engaged in certain actions/strategies that are categorized as "dealing with discordancy" such as entertaining partner's interest by scarifying once self interest to maintain their relationship. HIV discordant couples' relationship is filled with controversies of maintaining

  19. Archaeal dominated ammonia-oxidizing communities in Icelandic grassland soils are moderately affected by long-term N fertilization and geothermal heating

    Directory of Open Access Journals (Sweden)

    Anne eDaebeler

    2012-10-01

    Full Text Available The contribution of ammonia-oxidizing bacteria and archaea (AOB and AOA, respectively to the net oxidation of ammonia varies greatly between terrestrial environments. To better understand, predict and possibly manage terrestrial nitrogen turnover, we need to develop a conceptual understanding of ammonia oxidation as a function of environmental conditions including the ecophysiology of the associated organisms. We examined the discrete and combined effects of mineral nitrogen deposition and geothermal heating on ammonia-oxidizing communities by sampling soils from a long-term fertilisation site along a temperature gradient in Icelandic grasslands. Microarray, clone library and quantitative PCR analyses of the ammonia monooxygenase subunit A (amoA gene accompanied by physico-chemical measurements of the soil properties were conducted. In contrast to most other terrestrial environments, the ammonia-oxidizing communities consisted almost exclusively of archaea. Their bacterial counterparts proved to be undetectable by quantitative PCR suggesting AOB are only of minor relevance for ammonia oxidation in these soils. Our results show that fertilization and local, geothermal warming affected detectable ammonia-oxidizing communities, but not soil chemistry: only a subset of the detected AOA phylotypes was present in higher temperature soils and AOA abundance was increased in the fertilized soils, while the measured soil physico-chemical properties remained unchanged. Differences in distribution and structure of AOA communities were best explained by soil pH and clay content irrespective of temperature or fertilizer treatment in these grassland soils, suggesting that these factors have a greater potential for ecological niche-differentiation of AOA in soil than temperature and N fertilization.

  20. [Is it possible to obtain reliable information about the long-term effects of induced abortion?].

    Science.gov (United States)

    Iversen, Grete Alræk; Løkeland, Mette; Fjereide, Anneli Katrine; Bjørge, Line; Iversen, Ole-Erik

    2012-06-26

    The psychological long-term effects of an induced abortion are the subject of constant debate, but the scientific basis of experience is limited and by no means unambiguous. We wanted to study how a random selection of women felt about pre-agreed follow-up studies after an induced abortion. All abortion patients who attended the Department of Obstetrics and Gynaecology at Haukeland University Hospital during a three-month period received a questionnaire. They were asked if they would be willing to be contacted in writing with questions about long-term effects 1-2 years and 5-10 years after the intervention, and to give reasons for their decisions by setting crosses in the multiple choice responses that were listed. During the period of the study, 300 abortions were carried out at the department. Questionnaires were distributed to 227 of these patients, and 181 (80 %) of them were included. 43 % of the women in the study agreed to take part in a questionnaire survey concerning the long-term effects, if any, of induced abortion 1-2 years after the intervention, and 35 % 5-10 years afterwards. It appears that it may be difficult to study the psychological long-term effects of induced abortion by means of questionnaire surveys. Our results indicate that the percentage of participants in long-term studies would be too low, and hence not representative of the group as a whole.

  1. Biogeography and organic matter removal shape long-term effects of timber harvesting on forest soil microbial communities.

    Science.gov (United States)

    Wilhelm, Roland C; Cardenas, Erick; Maas, Kendra R; Leung, Hilary; McNeil, Larisa; Berch, Shannon; Chapman, William; Hope, Graeme; Kranabetter, J M; Dubé, Stephane; Busse, Matt; Fleming, Robert; Hazlett, Paul; Webster, Kara L; Morris, David; Scott, D Andrew; Mohn, William W

    2017-07-28

    The growing demand for renewable, carbon-neutral materials and energy is leading to intensified forest land-use. The long-term ecological challenges associated with maintaining soil fertility in managed forests are not yet known, in part due to the complexity of soil microbial communities and the heterogeneity of forest soils. This study determined the long-term effects of timber harvesting, accompanied by varied organic matter (OM) removal, on bacterial and fungal soil populations in 11- to 17-year-old reforested coniferous plantations at 18 sites across North America. Analysis of highly replicated 16 S rRNA gene and ITS region pyrotag libraries and shotgun metagenomes demonstrated consistent changes in microbial communities in harvested plots that included the expansion of desiccation- and heat-tolerant organisms and decline in diversity of ectomycorrhizal fungi. However, the majority of taxa, including the most abundant and cosmopolitan groups, were unaffected by harvesting. Shifts in microbial populations that corresponded to increased temperature and soil dryness were moderated by OM retention, which also selected for sub-populations of fungal decomposers. Biogeographical differences in the distribution of taxa as well as local edaphic and environmental conditions produced substantial variation in the effects of harvesting. This extensive molecular-based investigation of forest soil advances our understanding of forest disturbance and lays the foundation for monitoring long-term impacts of timber harvesting.The ISME Journal advance online publication, 28 July 2017; doi:10.1038/ismej.2017.109.

  2. The steroid-sparing effect of long-term plasmapheresis in pemphigus

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Carstens, Jan; Jørgensen, Jan

    1995-01-01

    Glucocorticoids and immunosuppressive agents can induce remission in most patients with pemphigus, but mortality remains at 5 to 15% due to complications from these drugs. We reviewed the adjunctive effect of long-term plasmapheresis in 8 patients with pemphigus. Four cases had been resistant to ...... where cyclosporine was introduced. This first report of long-term plasmapheresis demonstrates clinical efficacy in pemphigus and a considerable steroid-sparing effect.......Glucocorticoids and immunosuppressive agents can induce remission in most patients with pemphigus, but mortality remains at 5 to 15% due to complications from these drugs. We reviewed the adjunctive effect of long-term plasmapheresis in 8 patients with pemphigus. Four cases had been resistant...

  3. Effect of mold temperature on short and long-term mechanical properties of PBT

    Directory of Open Access Journals (Sweden)

    2008-02-01

    Full Text Available In this work, the effect of mold temperature variation on the short-term mechanical properties obtained from the tensile and Charpy impact tests, and the long-term mechanical properties obtained from dynamic mechanical loading and flexural creep of injection molded polybutylene terepthalate (PBT are reported. It has been observed that the effect of changing the processing condition viz. mold temperature on the viscoelastic properties are more pronounced when their long-term behavior is tested. The tensile and impact properties showed only a negligible effect to the change in mold temperature. Further, analysis of the creep curves by applying a four-element Burger model presented a comprehensive understanding of their long-term viscoelastic behavior with respect to the change in mold temperature.

  4. Long-term effects of a binary mixture of perfluorooctane sulfonate (PFOS) and bisphenol A (BPA) in zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Keiter, Susanne; Baumann, Lisa; Farber, H

    2012-01-01

    were generally found to decrease with increasing PFOS-exposure in both F1 and F2 generations. In F1 generation, BPA-exposure was found to increase Vtg levels in a concentration-dependent manner. Histological analyses of F1 and F2 fish revealed hepatocellular vacuolization, predominantly in males...... aimed at evaluating the long-term effects and toxicity-increasing behavior of PFOS in vivo using the zebrafish (Danio rerio). Fish were maintained in flow-through conditions and exposed to single and binary mixtures of PFOS and the endocrine disruptor bisphenol A (BPA) at nominal concentrations of 0.......6, 100 and 300mug/L and 10, 200 and 400mug/L, respectively. F1 and F2 generations were evaluated from 0 to 180 days post-fertilization (dpf) and F3 generation was evaluated from 0 to 14 dpf. Survival was documented in all generations, whereas growth, fecundity, fertilization rate, histological...

  5. Individual Differences in the Effects of Retrieval from Long-Term Memory

    Science.gov (United States)

    Brewer, Gene A.; Unsworth, Nash

    2012-01-01

    The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…

  6. The Long-Term Effects of Childhood Music Instruction on Intelligence and General Cognitive Abilities

    Science.gov (United States)

    Costa-Giomi, Eugenia

    2015-01-01

    This article reviews research on the effects of music instruction on general cognitive abilities. The review of more than 75 reports shows (1) the consistency in results pertaining to the short-term effects of music instruction on cognitive abilities and the lack of clear evidence on the long-term effects on intelligence; (2) the complex nature of…

  7. Individual Differences in the Effects of Retrieval from Long-Term Memory

    Science.gov (United States)

    Brewer, Gene A.; Unsworth, Nash

    2012-01-01

    The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…

  8. The Long-Term Effects of Childhood Music Instruction on Intelligence and General Cognitive Abilities

    Science.gov (United States)

    Costa-Giomi, Eugenia

    2015-01-01

    This article reviews research on the effects of music instruction on general cognitive abilities. The review of more than 75 reports shows (1) the consistency in results pertaining to the short-term effects of music instruction on cognitive abilities and the lack of clear evidence on the long-term effects on intelligence; (2) the complex nature of…

  9. Dissimilar response of plant and soil biota communities to long-term nutrient adition in grasslands

    NARCIS (Netherlands)

    Wal, van der A.; Geerts, R.H.E.M.; Korevaar, H.; Schouten, A.J.; Jagers op Akkerhuis, G.A.J.M.; Rutgers, M.; Mulder, C.

    2009-01-01

    The long-term effect of fertilizers on plant diversity and productivity is well known, but long-term effects on soil biota communities have received relatively little attention. Here, we used an exceptional long-lasting (>40 years) grassland fertilization experiment to investigate the long-term e

  10. EFFECTS OF LONG-TERM FERTILIZATION ON COMPOSITION AND FRACTAL FEATURE OF SOIL MICRO-AGGREGATES UNDER A WHEAT-MAIZE CROPPING SYSTEM%长期施肥对小麦-玉米轮作土壤微团聚体组成和分形特征的影响

    Institute of Scientific and Technical Information of China (English)

    龚伟; 颜晓元; 蔡祖聪; 王景燕

    2011-01-01

    The composition and fractal dimension (D) of micro-aggregates in 0 ~ 20 cm soil layer were studied on a long-term fertilized field under wheat-maize cropping rotation in North China Plain, and relationships of soil fertility with compositional proportion of characteristic soil micro-aggregates (PCM , < 20 μm/(250 ~ 20) μm) , ratio of the content of < 20 μm particle-size to the content of 2 000 ~ 20 μm particle-size content in soil micro-aggregates determination (RMD, <20 μm/(2 000 ~20)μm) and D were evaluated. The long-term fertilization experiment was designed to include 7 treatments: fertilizer NPK (NPK) , organic manure (OM), half organic manure with chemical fertilizer NPK (1/20MN), chemical fertilizer NP (NP), chemical fertilizer PK (PK) , chemical fertilizer NK (NK) and control (CK). After 18 years of fertilization, all the treatments, except CK showed lower values of PCM, RMD and D, and higher nutrients content and enzyme activity. Among the fertilization treatments, Treatment OM was the lowest in PCM,RMD and D, followed by Treatment 1/20MN, and the treatments with chemical fertilizers. Balanced application of fertilizers (Treatment NPK) was lower in PCM,RMD and D than imbalanced use of fertilizers (Treatments NP, PK, and NK). PCM, RMD and D were closely related to crop yield, soil organic matter, hydrolysis N, and enzyme activity. The findings indicate that the use of organic manure alone or in combination with fertilizer NPK and balanced application of fertilizer NPK are key to improving soil micro-aggregate composition, decreasing PCM, RMD and D, and increasing soil nutrient preserving and supplying capacity; and that PCM, RMD and D can be used as integrated quantitative indexes to evaluate the soil fertility under a long-term fertilization cropping system.%通过对华北平原小麦-玉米轮作农田生态系统18 a田间施肥试验,研究了长期不同施肥处理对耕层(0 ~20 cm)土壤微团聚体组成及分形维数(D)的影

  11. The science of cellulite treatment and its long-term effectiveness.

    Science.gov (United States)

    Wassef, Cindy; Rao, Babar K

    2012-04-01

    Cellulite is a disorder in which adipose tissue extends through the dermis, producing a cosmetically displeasing dimpling in the affected areas. While many treatments claim to be able to improve the appearance of cellulite, the long-term effectiveness of these treatments and whether the logic behind these treatments can lead to a long-term improvement has not been extensively reviewed. In the following review, our goal is to assess the various cellulite treatments and evaluate the length of time results persist and whether the science behind the treatments warrants them as reliable and effective treatments for cellulite.

  12. Short- and Long-Term Effects of Adolescent Alcohol Access: Evidence from Denmark

    DEFF Research Database (Denmark)

    Gupta, Nabanita Datta; Nilsson, Anton; Kedir, Abdu

    We exploit changes in minimum legal alcohol purchasing ages in Denmark in order to estimate effects on short- and long-term health outcomes, as well as on human capital formation. Employing a difference-in-differences approach for immediate outcomes and a “regression kink design” for long......-term outcomes, we bring comprehensive evidence on the health and education effects of three reforms, which affected alcohol availability along different dimensions and margins – 1) establishing an off-premise alcohol purchase age of 15 (1998), 2) raising the off-premise alcohol purchase age to 16 (2004), and 3...

  13. Cascading effects of long-term land-use changes on plant traits and ecosystem functioning.

    Science.gov (United States)

    Laliberté, Etienne; Tylianakis, Jason M

    2012-01-01

    There is much concern that the functioning of ecosystems will be affected by human-induced changes in biodiversity, of which land-use change is the most important driver. However, changes in biodiversity may be only one of many pathways through which land use alters ecosystem functioning, and its importance relative to other pathways remains unclear. In particular, although biodiversity-ecosystem function research has focused primarily on grasslands, the increases in agricultural inputs (e.g., fertilization, irrigation) and grazing pressure that drive change in grasslands worldwide have been largely ignored. Here we show that long-term (27-year) manipulations of soil resource availability and sheep grazing intensity caused marked, consistent shifts in grassland plant functional composition and diversity, with cascading (i.e., causal chains of) direct, indirect, and interactive effects on multiple ecosystem functions. Resource availability exerted dominant control over above-ground net primary production (ANPP), both directly and indirectly via shifts in plant functional composition. Importantly, the effects of plant functional diversity and grazing intensity on ANPP shifted from negative to positive as agricultural inputs increased, providing strong evidence that soil resource availability modulates the impacts of plant diversity and herbivory on primary production. These changes in turn altered litter decomposition and, ultimately, soil carbon sequestration, highlighting the relevance of ANPP as a key integrator of ecosystem functioning. Our study reveals how human alterations of bottom-up (resources) and top-down (herbivory) forces together interact to control the functioning of grazing systems, the most extensive land use on Earth.

  14. Helium irradiation effects on tritium retention and long-term tritium release properties in polycrystalline tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Nobuta, Y., E-mail: y-nobuta@eng.hokudai.ac.jp [Laboratory of Plasma Physics and Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Hatano, Y.; Matsuyama, M.; Abe, S. [Hydrogen Isotope Research Center, University of Toyama, Gofuku 3190, Toyama 930-8555 (Japan); Yamauchi, Y.; Hino, T. [Laboratory of Plasma Physics and Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo 060-8628 (Japan)

    2015-08-15

    DT{sup +} ion irradiation with energy of 0.5 and 1.0 keV was performed on helium pre-irradiated tungsten and the amount of retained tritium and the long-term release of retained tritium in vacuum was investigated using an IP technique and BIXS. Tritium retention and long-term tritium release were significantly influenced by helium pre-irradiation. The amount of retained tritium increased until it reached 1 × 10{sup 17} He/cm{sup 2}, and at 1 × 10{sup 18} He/cm{sup 2} it became smaller compared to 1 × 10{sup 17} He/cm{sup 2}. The amount of retained tritium in tungsten without helium pre-irradiation largely decreased after several weeks preservation in vacuum, and the long-term release rate during vacuum preservation was retarded by helium pre-irradiation. The results indicate that the long-term tritium release and the helium irradiation effect on it should be taken into account for more precise estimation of tritium retention in the long-term use of tungsten in fusion devices.

  15. [Effects of long-term Tai Ji Quan exercise on automatic nervous modulation in the elderly].

    Science.gov (United States)

    Guo, Feng

    2015-03-01

    To examine the effects of long-term Tai Ji Quan (Chinnese Traditional Exercise) on automatic nervous modulation in the elders. The 18 subjects from Tai Ji Quan exercise class in Liaoning University of Retired Veteran Cadres were assigned into long-term Tai Ji Quan exercise group including 10 subjects and novice group including 8 subjects. Electrocardiography, respiratory and blood pressure data were collected on the following time points: at rest before Tai Ji Qhuan exercise and 30 min or 60 min after Tai Ji Quan exercise. The subjects at rest state in the long-term Tai Ji Quan exercise group showed higher than the subjects in the novice group in resperitory rate (RR), standard deviations of normal to normal intervals (SDNN), total power (TP), low frequency power (LFP), high frequency power (HFP), normalized high frequency power (nHFP), but lower in LFP/HFP, systolic and diastolic blood pressure, and heart rate. At rest state the respiratory rate of subjects in long-term Tai Ji Quan exercise group was significantly lower than the novices. After Tai Ji Quan exercise, TP, nHFP, LFP/HFP, heart rate and systolic pressure showed significantly changes, and the change level of Tai Ji Quan on these indices was larger in Tai Ji Quan exercise group than that in the novice group. Long-term Tai Ji Quan exercise can improve vagal modulations, and tend to reduce the sympathetic modulations.

  16. Changes in soil carbon and enzyme activity as a result of different long-term fertilization regimes in a greenhouse field.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    Full Text Available In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C transformations, soil chemical characteristics, and crop yields were monitored after long-term (20-year fertilization regimes, including no fertilizer (CK, 300 kg N ha-1 and 600 kg N ha-1 as urea (N1 and N2, 75 Mg ha-1 horse manure compost (M, and M with either 300 or 600 kg N ha-1 urea (MN1 and MN2. Compared with CK, fertilization increased crop yields by 31% (N2 to 69% (MN1. However, compared with CK, inorganic fertilization (especially N2 also caused soil acidification and salinization. In the N2 treatment, soil total organic carbon (TOC decreased from 14.1±0.27 g kg-1 at the beginning of the long-term experiment in 1988 to 12.6±0.11 g kg-1 (P<0.05. Compared to CK, N1 and N2 exhibited higher soil α-galactosidase and β-galactosidase activities, but lower soil α-glucosidase and β-glucosidase activities (P<0.05, indicating that inorganic fertilization had different impacts on these C transformation enzymes. Compared with CK, the M, MN1 and MN2 treatments exhibited higher enzyme activities, soil TOC, total nitrogen, dissolved organic C, and microbial biomass C and N. The fertilization regime of the MN1 treatment was identified as optimal because it produced the highest yields and increased soil quality, ensuring sustainability. The results suggest that inorganic fertilizer alone, especially in high amounts, in greenhouse fields is detrimental to soil quality.

  17. Sustainability of teacher expectation bias effects on long-term student performance

    NARCIS (Netherlands)

    de Boer, Hester; Bosker, R.J.; Van der Werf, M.P.C.

    2010-01-01

    In this article, we address the relationship between teacher expectation bias and student characteristics, its effect on long-term student performance, and the development of this effect over time. Expectation bias was defined as the difference between observed and predicted teacher expectation. The

  18. Sustainability of teacher expectation bias effects on long-term student performance

    NARCIS (Netherlands)

    de Boer, Hester; Bosker, R.J.; Van der Werf, M.P.C.

    2010-01-01

    In this article, we address the relationship between teacher expectation bias and student characteristics, its effect on long-term student performance, and the development of this effect over time. Expectation bias was defined as the difference between observed and predicted teacher expectation. The

  19. Sustainability of Teacher Expectation Bias Effects on Long-Term Student Performance

    Science.gov (United States)

    de Boer, Hester; Bosker, Roel J.; van der Werf, Margaretha P. C.

    2010-01-01

    In this article, we address the relationship between teacher expectation bias and student characteristics, its effect on long-term student performance, and the development of this effect over time. Expectation bias was defined as the difference between observed and predicted teacher expectation. These predicted expectations were estimated from a…

  20. Long-term effects of a home-visiting intervention for depressed mothers and their infants

    NARCIS (Netherlands)

    Kersten-Alvarez, L.E.; Hosman, C.M.H.; Riksen-Walraven, J.M.A.; Doesum, K.T.M. van; Hoefnagels, C.C.J.

    2010-01-01

    Background - Whereas preventive interventions for depressed mothers and their infants have yielded positive short-term outcomes, few studies have examined their long-term effectiveness. The present follow-up of a randomised controlled trial (RCT) is one of the first to examine the longer-term effect

  1. Effects of long-term grazing on sediment deposition and salt-marsh accretion rates

    NARCIS (Netherlands)

    Elschot, K.; Bouma, T.J.; Temmerman, S.; Bakker, J.P.

    2013-01-01

    Many studies have attempted to predict whether coastal marshes will be able to keep up with future acceleration of sea-level rise by estimating marsh accretion rates. However, there are few studies focussing on the long-term effects of herbivores on vegetation structure and subsequent effects on mar

  2. Naturalistic Studies of the Long-Term Effects of Television Violence.

    Science.gov (United States)

    Turner, Charles W.; And Others

    1986-01-01

    Argues that field research can provide evidence about the long-term socialization and developmental effects of media violence on viewer's behavior. Summarizes findings from a number of quasi-experimental studies about the effects of naturally occurring media violence. Concludes that these findings are often consistent with the hypothesis that…

  3. Long-term semantic representations moderate the effect of attentional refreshing on episodic memory.

    Science.gov (United States)

    Loaiza, Vanessa M; Duperreault, Kayla A; Rhodes, Matthew G; McCabe, David P

    2015-02-01

    The McCabe effect (McCabe, Journal of Memory and Language 58:480-494, 2008) refers to an advantage in episodic memory (EM) retrieval for memoranda studied in complex span versus simple span tasks, particularly for memoranda presented in earlier serial positions. This finding has been attributed to the necessity to refresh memoranda during complex span tasks that, in turn, promotes content-context binding in working memory (WM). Several frameworks have conceptualized WM as being embedded in long-term memory. Thus, refreshing may be less efficient when memoranda are not well-established in long-term semantic memory (SM). To investigate this, we presented words and nonwords in simple and complex span trials in order to manipulate the long-term semantic representations of the memoranda with the requirement to refresh the memoranda during WM. A recognition test was administered that required participants to make a remember-know decision for each memorandum recognized as old. The results replicated the McCabe effect, but only for words, and the beneficial effect of refreshing opportunities was exclusive to recollection. These results extend previous research by indicating that the predictive relationship between WM refreshing and long-term EM is specific to recollection and, furthermore, moderated by representations in long-term SM. This supports the predictions of WM frameworks that espouse the importance of refreshing in content-context binding, but also those that view WM as being an activated subset of and, therefore, constrained by the contents of long-term memory.

  4. Seasonal differences in tillage draught on a sandy loam soil with long-term additions of animal manure and mineral fertilizers

    DEFF Research Database (Denmark)

    Peltre, Clément; Nyord, T.; Christensen, B.T.;

    2016-01-01

    Energy requirements for soil tillage are closely linked to soil properties, such as clay, water and soil organic carbon (SOC) contents. Long-term application of inorganic fertilizer and organic amendments affects SOC content but little is known about seasonal differences in tillage draught...... requirements of soils subject to contrasting nutrient management regimes. We assessed autumn and spring tillage draught following harvest of early-sown and timely sown winter wheat grown on a sandy loam in the Askov Long-Term Experiment on Animal Manure and Mineral Fertilizers. Draught force was related...... to soil texture, soil water and SOC content, shear strength and bulk density, nutrient management, and yield of the preceding winter wheat. Contents of clay and SOC ranged from 8.9 to 10.6% and from 0.98 to 1.36%, respectively. In the autumn and spring, SOC normalized by clay content explained 38 and 5...

  5. Organic Amendment Effects on Greenhouse Gas Emissions from Long-Term Stockpiled Soils

    Science.gov (United States)

    Zvomuya, F.; Laskosky, J.

    2014-12-01

    In oil sands projects in Alberta, Canada, salvaged soils are often placed in large stockpiles where they are stored for the duration of the project, typically 20-30 years. Alberta regulations require that topsoil and subsoil are salvaged in two distinct operations - a process known as two-lifting. Reclamation using long-term stockpiled soils often gives poor results, characterized by lower soil organic carbon and nitrogen concentrations compared with equivalent natural, undisturbed soils. It is thought that the change from an aerobic to an anaerobic environment during soil stockpiling and back again to aerobic during placement are largely responsible for the low carbon and nitrogen due to microbial activity transforming C and N in the soil into CO2, CH4 and N2O and releasing them to the atmosphere. Evidence from recent studies indicates that biochar improves soil physical, chemical and biological properties, and hence could mitigate C and N losses due to greenhouse gas emissions from the soil indirectly. We postulate that documented improvements in soil physical, chemical, and biological properties in soils treated with amendments such as biochar may help mitigate C and N losses due to greenhouse gas emissions from the soil indirectly. This laboratory incubation experiment tested the effects of differential rates (0, 10, 20, and 40 g biochar carbon equivalents kg-1 dry soil) of biochar, peat, and humalite on greenhouse gas emissions from a 25-year old two-lift stockpiled soil. The soils were fertilized according to standard practice, placed in 120-mL plastic containers, and incubated at 25°C for 45 days. Gas samples were taken at 1- to 7-day intervals and analyzed for CO2, CH4, and N2O. Data on treatment differences in emissions will be presented. Results from this experiment will provide an insight into the potential for organic amendments to mitigate greenhouse gas emission during reclamation using degraded soils.

  6. Autoimmune hepatitis as an adverse effect of long-term methotrexate therapy

    Directory of Open Access Journals (Sweden)

    Kamilia Ksouda

    2014-01-01

    Full Text Available Methotrexate (MTX is one of the most commonly used medicines in the treatment of psoriatic arthritis. The drug can produce steatosis and cirrhosis. Autoimmune hepatitis is a rare and serious adverse effect. We describe the case of a 53-year-old woman who developed autoimmune hepatitis after a long-term use of MTX for psoriatic arthritis. Hepatitis was completely resolved 4 months after stopping this drug. The pathophysiologic mechanisms of a drug-induced autoimmunity are unclear and complex. This report confirms the need to monitor liver enzymes carefully in patients using long-term treatment with MTX for psoriasis or rheumatoid arthritis.

  7. Short- and Long-Term Effects of Concurrent Strength and HIIT Training in Octogenarians with COPD.

    Science.gov (United States)

    Guadalupe-Grau, Amelia; Aznar-Laín, Susana; Mañas, Asier; Castellanos, Juan; Alcázar, Julián; Ara, Ignacio; Mata, Esmeralda; Daimiel, Rosa; García-García, Francisco José

    2017-01-01

    To investigate the short- and long-term effects of concurrent strength and high-intensity interval training (HIIT) on octogenarian COPD patients, nine males (age = 84.2 ± 2.8 years, BMI = 29.3 ± 2.3) with low to severe COPD levels (2.1 ± 1.5 BODE index) underwent a supervised 9-week strength and HIIT exercise program. Training had a significant (p HIIT training increases physical fitness in the oldest-old COPD patients, and has potential long-term benefits.

  8. Effects of long-term blindness on preparatory emg modulation in humans performing landing movements.

    Science.gov (United States)

    Magalhães, Fernando Henrique; Goroso, Daniel Gustavo

    2011-10-01

    To investigate the long-term effect of blindness on the task of leaping down to a lower landing surface, five blind individuals were compared with 10 sighted individuals who performed landing movements with and without sight. Participants performed six consecutive drop-landings from four different heights, during which the prelanding modulation of EMG timing and amplitude in four lower-limb muscles were recorded. Analysis showed that blind individuals showed specific prelanding EMG modulation, suggesting that long-term dependence on somesthetic and vestibular cues leads to different preparatory measures for vertical falls.

  9. Effects of long-term fertilization on spring season weed community in winter fallow paddy field in red soil area under double-rice cropping system%长期施肥对红壤双季稻冬闲田春季杂草群落的影响

    Institute of Scientific and Technical Information of China (English)

    董春华; 曾希柏; 石林; 高菊生

    2015-01-01

    利用始于1982年的红壤双季稻田长期施肥定位试验,于2012年采用田间调查法研究了在无机肥(化肥 NPK)与有机肥(M)氮磷钾养分等量条件下,长期施用有机肥、无机化肥和有机肥无机肥配施模式下红壤双季稻冬闲田春季杂草生物量及群落密度和群落多样性的变化。结果表明:有机肥无机肥配施改变了优势杂草种类,增加了杂草总密度和总生物量。化肥氮钾配施有机肥(NKM)处理的杂草种类数量最多,化肥氮磷配施有机肥(NPM)处理的最少。施肥处理中, M处理的杂草群落多样性指数、均匀度指数和优势度指数均最高,分别为1.1186、0.7323和0.6297;其杂草总密度最低,为297.0株×0.25m-2。NPK处理的杂草总生物量最低,为58.0 g×0.25m-2。NPM处理的杂草群落多样性指数值、均匀度及优势度指数值均显著低于其他处理;其杂草总密度和杂草总生物量均最高,分别为539.7株×0.25m-2和109.5 g×0.25m-2;其优势杂草日本看麦娘的密度为428.0株×0.25m-2,相对密度为79.31%,明显高于其他处理优势杂草的密度和相对密度。春季杂草总干物质量与土壤碱解氮正相关(相关系数为0.703),与土壤 pH 负相关(相关系数为0.697),相关性不显著;与土壤有效磷显著正相关(相关系数为0.758*)。长期不同施肥模式下红壤稻田磷素是导致田间春季杂草群落特征变化的主要因素,通过改变土壤有效磷和碱解氮含量及土壤pH,能有效调控红壤双季稻冬闲田春季杂草生物量及群落密度和生物多样性。%An investigation in winter fallow field of double-rice cropping system in the red soil area was carried out in 2012 in a long-term fertilization experiment (started in 1982) site in Hengyang Red Soil Experiment Station of Chinese Academy of Agricultural Sciences to study the species, biomass and biodiversity of weed communities during spring season. The investigated long-term

  10. Effects of long-term N fertilizer application and liming on nitrification and ammonia oxidizers in acidic soils%长期施加氮肥及氧化钙调节对酸性土壤硝化作用及氨氧化微生物的影响

    Institute of Scientific and Technical Information of China (English)

    张苗苗; 王伯仁; 李冬初; 贺纪正; 张丽梅

    2015-01-01

    High levels of N fertilization and acid deposition could cause soil acidification directly and indirectly. The nitrogen cycle, especially nitrification, makes a great contribution to the acidification of agricultural soils across China, which further leads to the mobilization of potentially toxic metals such as aluminum ( Al ) and manganese ( Mn ) and decerases crop yields. Chemicals ( e. g., CaO) are amended as soil conditioners to relieve soil acidification. Ammonia oxidation, the rate-limiting step in the nitrification process, is driven by ammonia-oxidizing bacteria ( AOB) and ammonia-oxidizing archaea ( AOA) . Increasing evidence demonstrates that pH is one of the most important factors determining the niche separation of AOA and AOB, and AOA play the more important role in nitrification of acidic soils. However, abundant AOB have been detected in acidic soils but little is known about their ecological function. In this study, the effects of long-term N fertilization practices and liming on nitrification and ammonia oxidizers in acidic soils were investigated using quantitative PCR and DGGE methods combined with soil physiochemical analysis. Compared with a previous study conducted 6 years ago at the same site, N fertilizer application without liming further decreased soil pH (3.35—3.47) and potential nitrification rate (PNR) (0.02—0.14 μg NO-2-N g-1 soil h-1), while 2 years liming alleviated soil acidification (pH 4.10—4.46) and increased PNR (0.22—0.34μg NO-2-N g-1 soil h-1) significantly. There was a significantly positive correlation between soil pH and PNR, indicating the increase in soil pH via liming had positive effects on nitrification in acidic soils. AOA amoA gene copy numbers ( 7. 40 × 107—4. 08 × 108 copies/g ) were significantly higher than their counterpart AOB (1.67 × 106—2.57 × 107 copies/g) in soils that received different chemical N fertilizers. Ratios of AOA and AOB amoA gene abundance ranged between 10. 9 and 44. 3

  11. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats.

    Directory of Open Access Journals (Sweden)

    Vanessa Manchim Favaro

    Full Text Available Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM, fear conditioning and elevated plus maze (EPM performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes.

  12. Effect of water on long-term weakening preceding rupture of crustal faults

    Science.gov (United States)

    Masuda, K.; Arai, T.; Fujimoto, K.; Takahashi, M.; Shigematsu, N.

    2010-12-01

    Fault strength is a critical parameter in studies of crustal mechanics and for the prediction of earthquake hazards. The strengths of crustal faults inferred from borehole heat flow measurements and maximum stress orientations in the crust are less than those determined from laboratory measurements. Suggested causes of the weakening of faults include high fluid pressures, dynamic processes, or the presence of weak fault gouge. However, long-term changes of fault strength cannot be directly monitored using geophysical techniques, so an explanation for fault weakening remains an unsolved problem. We provide laboratory evidence that long-term weakening of the frictional strength of faults is caused by micro-fracturing at asperity contacts, which is a result of crack growth at subcritical stress levels. Our model suggests that long-term reductions of fault strength are related to chemical reactions that take place in the presence of water. For our measurements of friction on rupture surfaces in the presence of water, we increased temperatures to accelerate reaction processes so that they were observable at laboratory time-scales. In the presence of water, frictional strength decreased as temperature increased, whereas it changed little in the absence of water. The observed decreases in frictional strength were facilitated by chemical processes, rather than by physical processes governed by the effective pressure law. These observations suggest that chemical processes such as stress corrosion play an important role in long-term fault weakening. In addition to long-term monitoring of fault zones, we need to investigate long-term processes that cannot be observed during a human lifetime if we are to understand earthquake occurrences in the deep crust.

  13. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

    Science.gov (United States)

    Favaro, Vanessa Manchim; Yonamine, Maurício; Soares, Juliana Carlota Kramer; Oliveira, Maria Gabriela Menezes

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM), fear conditioning and elevated plus maze (EPM) performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes. PMID:26716991

  14. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats.

    Science.gov (United States)

    Favaro, Vanessa Manchim; Yonamine, Maurício; Soares, Juliana Carlota Kramer; Oliveira, Maria Gabriela Menezes

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM), fear conditioning and elevated plus maze (EPM) performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes.

  15. EFFECT OF LONG-TERM FERTILIZATION, STUBBLE MULCH AND IRRIGATION UNDER DIFFERENT FERTILIZATION ON SOIL ENZYME AND SOIL NUTRIENTS%长期施肥及不同施肥条件下秸秆覆盖、灌水对土壤酶和养分的影响

    Institute of Scientific and Technical Information of China (English)

    王改玲; 李立科; 郝明德; 洪坚平

    2012-01-01

    以陕西省合阳县的28年定位试验为依托,通过主成分分析和聚类分析,研究了施肥及不同施肥条件下秸秆覆盖、灌水对土壤脲酶、磷酸酶、转化酶、过氧化氢酶活性和土壤养分含量的影响。结果表明,NP肥施用对土壤脲酶无显著影响,而使磷酸酶、转化酶活性分别较对照提高119.6%和22.0%,NP有机肥(NPM肥)使脲酶、磷酸酶、转化酶活性分别较对照提高53.2%、130.8%和60.6%,NPM肥的作用大于NP肥;秸秆覆盖和灌水对脲酶、磷酸酶、转化酶活性的影响因施肥条件不同而表现不同;NP肥能提高土壤速效氮、速效磷和全氮含量,NP肥施用基础上灌水能提高土壤有机质、碱解氮和速效磷含量,NPM肥施量、NP肥及NPM肥施用基础上秸秆覆盖均能显著提高土壤有机质、碱解氮、速效磷、速效钾、全氮和全磷含量,其中速效磷的提高幅度最大,NPM肥较对照提高64.4mg/kg,NPM肥基础上秸秆覆盖使速效磷含量较施用NPM肥提高44.0mg/kg,施肥、秸秆覆盖和灌水对土壤全钾含量和过氧化氢酶活性影响总体上不显著。主成分分析和聚类分析表明,NPM肥和NPM肥结合灌水更有利于土壤养分和酶活性综合因子的提高,提高土壤肥力;秸秆覆盖有利于提高土壤养分,不利于酶活性综合因子的提高;灌水的影响较小。生产上应注意大量秸秆覆盖对土壤酶活性的不利影响。%On the basis of the 28-year experiment located in Heyang County, Shaanxi Province, effects of fertilization, stubble mulch and irrigation under different fertilization on soil urease, phosphatase, invertase, hydrogen peroxidase activities and contents of soil nutrients were studied through principal component analysis and cluster analysis. Results were as follows: the activities of Urease was not influenced by NP treatment, the activities of phosphatase and invertase increased 119.6% and 22.0% by NP treatment respectively. The

  16. The long-term effects of bilingualism on children of immigration: student bilingualism and future earnings

    NARCIS (Netherlands)

    Agirdag, O.

    2014-01-01

    In this study, we examine the largely neglected long-term effects of bilingualism for students with roots in immigration. Our central research question is whether students' bilingual proficiencies have an impact on their future earnings in the USA. For this purpose, we used two different data-sets,

  17. Scarring Effects of Remaining Unemployed for Long-Term Unemployed School-Leavers

    NARCIS (Netherlands)

    Cockx, B.; Picchio, M.

    2011-01-01

    This study investigates whether and to what extent further unemployment experience for youths who are already long-term unemployed imposes a penalty on subsequent labor market outcomes. We propose a flexible method for analyzing the effect on wages aside of transitions from unemployment and employme

  18. Long-term health effects on the next generation of Ramadan fasting during pregnancy

    NARCIS (Netherlands)

    van Ewijk, R.

    2009-01-01

    Each year, many pregnant women fast from dawn to sunset during the Islamic holy month of Ramadan. Medical theory suggests that this may have negative long-term health effects on their offspring. Building upon the work of Almond and Mazumder (2008), and using Indonesian crosssectional data, I show th

  19. Long term effects of parenting and family characteristics on delinquency of male young adults

    NARCIS (Netherlands)

    Hoeve, M.; Smeenk, W.; Loeber, R.; Southamer-Loeber, M.; van der Laan, P.H.; Gerris, J.R.; Dubas, J.S.

    2007-01-01

    Drawing from the criminology literature and family studies, we investigated the long-term effects of established family risk factors and parenting styles on male young adult delinquency. We used data sets from two longitudinal studies, the Pittsburgh Youth Study (N474) and the Child-Rearing and

  20. The Long-Term Effects of Housing Assistance on Work and Welfare

    Science.gov (United States)

    Newman, Sandra; Holupka, C. Scott; Harkness, Joseph

    2009-01-01

    This paper examines the long-term effect of project-based housing assistance--public housing and private assisted housing--on work, earnings, and welfare receipt. We use the Panel Study of Income Dynamics-Assisted Housing Database to identify women ever living in project-based assisted housing and to create comparison groups using propensity…

  1. Effect of Long-Term Physical Activity Practice after Cardiac Rehabilitation on Some Risk Factors

    Science.gov (United States)

    Freyssin, Celine, Jr.; Blanc, Philippe; Verkindt, Chantal; Maunier, Sebastien; Prieur, Fabrice

    2011-01-01

    The objective of this study was to evaluate the effects of long-term physical activity practice after a cardiac rehabilitation program on weight, physical capacity and arterial compliance. The Dijon Physical Activity Score was used to identify two groups: sedentary and active. Weight, distance at the 6-min walk test and the small artery elasticity…

  2. Long-term effects of climate change on vegetation and carbon dynamics in peat bogs

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.; Mauquoy, D.; van Geel, B.; Berendse, F.

    2008-01-01

    Questions: What are the long-term effects of climate change on the plant species composition and carbon sequestration in peat bogs? Methods: We developed a bog ecosystem model that includes vegetation, carbon, nitrogen and water dynamics. Two groups of vascular plant species and three groups of Spha

  3. Long-Term Knowledge Effects on Serial Recall of Nonwords Are Not Exclusively Lexical

    Science.gov (United States)

    Thorn, Annabel S. C.; Frankish, Clive R.

    2005-01-01

    S. Roodenrys and M. Hinton (2002) reported superior recall for nonwords with large rather than small lexical neighborhoods when constituent biphone frequency was controlled, but comparable recall of high and low biphone frequency nonwords when neighborhood size was controlled, suggesting that long-term knowledge effects on nonword recall are…

  4. Long-term effects of climate change on Europe's water resources

    NARCIS (Netherlands)

    Domnisoru, A.

    2006-01-01

    Climate variations from last century show a global warming trend. Evidence from the past reveals that the anthropogenic greenhouse effect caused changes in climate parameters (temperature, precipitation and evaporation) at the European scale as well. On long-term this might have essential impact on

  5. Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers

    NARCIS (Netherlands)

    Renkema, Anne-Marie; Renkema, Alianne; Bronkhorst, Ewald; Katsaros, Christos

    2011-01-01

    Introduction: The flexible spiral wire (FSW) canine-to-canine lingual retainer bonded to all 6 anterior teeth is a frequently used type of mandibular fixed retainer. This study aimed to assess the long-term effectiveness of FSW canine-to-canine lingual retainers in maintaining the alignment of the m

  6. Long-Term Effects of a Personality-Targeted Intervention to Reduce Alcohol Use in Adolescents

    Science.gov (United States)

    Conrod, Patricia J.; Castellanos-Ryan, Natalie; Mackie, Clare

    2011-01-01

    Objective: To examine the long-term effects of a personality-targeted intervention on drinking quantity and frequency (QF), problem drinking, and personality-specific motivations for alcohol use in early adolescence. Method: A randomized control trial was carried out with 364 adolescents (median age 14) recruited from 13 secondary schools with…

  7. Unhappily Ever After: Effects of Long-Term, Low-Quality Marriages on Well-Being

    Science.gov (United States)

    Hawkins, Daniel N.; Booth, Alan

    2005-01-01

    The present study shows that long-term, low-quality marriages have significant negative effects on overall well-being. We utilize a nationally representative longitudinal study with a multi-item marital quality scale that allows us to track unhappy marriages over a 12-year period and to assess marital happiness along many dimensions. Remaining…

  8. Long-term effectiveness of sphenopalatine ganglion stimulation for cluster headache

    DEFF Research Database (Denmark)

    Jürgens, Tim P; Barloese, Mads; May, Arne

    2017-01-01

    OBJECTIVES: The sphenopalatine ganglion (SPG) plays a pivotal role in cluster headache (CH) pathophysiology as the major efferent parasympathetic relay. We evaluated the long-term effectiveness of SPG stimulation in medically refractory, chronic CH patients. METHODS: Thirty-three patients were...

  9. Long-Term Effect of Prefrontal Lobotomy on Verbal Fluency in Patients with Schizophrenia

    Science.gov (United States)

    Stip, Emmanuel; Bigras, Marie-Josee.; Mancini-Marie, Adham; Cosset, Marie-Eve.; Black, Deborah; Lecours, Andre-Roch

    2004-01-01

    Objective: This study investigated the long-term effects of bilateral prefrontal leukotomy on lexical abilities in schizophrenia subjects. Method: We compared performances of leukotomized (LSP), non-leukotomized schizophrenia patients (NLSP) and normal controls, using a test of verbal fluency. Multiple case and triple comparison design were…

  10. Acute and long-term cardiovascular effects of coffee: implications for coronary heart disease.

    NARCIS (Netherlands)

    Riksen, N.P.; Rongen, G.A.P.J.M.; Smits, P.

    2009-01-01

    Despite decades of research, the question as to whether coffee intake increases the risk of coronary heart disease (CHD) remains controversial. In the current paper, we discuss the acute and long-term cardiovascular effects of coffee, and its major constituents, which could underlie such an

  11. Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers

    NARCIS (Netherlands)

    Renkema, A.M.; Bronkhorst, E.M.; Katsaros, C.

    2011-01-01

    INTRODUCTION: The flexible spiral wire (FSW) canine-to-canine lingual retainer bonded to all 6 anterior teeth is a frequently used type of mandibular fixed retainer. This study aimed to assess the long-term effectiveness of FSW canine-to-canine lingual retainers in maintaining the alignment of the m

  12. The long-term effects of bilingualism on children of immigration: student bilingualism and future earnings

    NARCIS (Netherlands)

    Agirdag, O.

    2014-01-01

    In this study, we examine the largely neglected long-term effects of bilingualism for students with roots in immigration. Our central research question is whether students' bilingual proficiencies have an impact on their future earnings in the USA. For this purpose, we used two different data-sets,

  13. The Long-Term Effects of Bilingualism on Children of Immigration: Student Bilingualism and Future Earnings

    Science.gov (United States)

    Agirdag, Orhan

    2014-01-01

    In this study, we examine the largely neglected long-term effects of bilingualism for students with roots in immigration. Our central research question is whether students' bilingual proficiencies have an impact on their future earnings in the USA. For this purpose, we used two different data-sets, i.e. the National Education Longitudinal…

  14. Long term effects of parenting and family characteristics on delinquency of male young adults

    NARCIS (Netherlands)

    Hoeve, M.; Smeenk, W.; Loeber, R.; Southamer-Loeber, M.; van der Laan, P.H.; Gerris, J.R.; Dubas, J.S.

    2007-01-01

    Drawing from the criminology literature and family studies, we investigated the long-term effects of established family risk factors and parenting styles on male young adult delinquency. We used data sets from two longitudinal studies, the Pittsburgh Youth Study (N474) and the Child-Rearing and Fami

  15. The long-term effect of social comparison on academic performance

    NARCIS (Netherlands)

    Wehrens, Maike J. P. W.; Kuyper, Hans; Dijkstra, Pieternel; Buunk, Abraham P.; van der Werf, Margaretha P. C.

    2010-01-01

    The present study was part of a large-scale cohort study among several thousand students in the Netherlands. The purpose of the study was to investigate the long-term effects of comparison choice, i.e., comparison with a target performing better or worse than oneself, and academic comparative evalua

  16. Long-term effects of climate change on Europe's water resources

    OpenAIRE

    Domnisoru, A.

    2006-01-01

    Climate variations from last century show a global warming trend. Evidence from the past reveals that the anthropogenic greenhouse effect caused changes in climate parameters (temperature, precipitation and evaporation) at the European scale as well. On long-term this might have essential impact on temporal and spatial distribution of water resources.

  17. Long-term effects of perinatal glucocorticoid treatment on the heart

    NARCIS (Netherlands)

    Vries, W.B. de

    2006-01-01

    Long-term effects of perinatal glucocorticoid treatment on the heart Chronic lung disease in the extremely preterm baby is still a major complication in neonatal intensive care medicine. Perinatal (ante- and neonatal) glucocorticoids are widely used to prevent severe infant respiratory syndrome and

  18. Acute and long-term cardiovascular effects of coffee: implications for coronary heart disease.

    NARCIS (Netherlands)

    Riksen, N.P.; Rongen, G.A.P.J.M.; Smits, P.

    2009-01-01

    Despite decades of research, the question as to whether coffee intake increases the risk of coronary heart disease (CHD) remains controversial. In the current paper, we discuss the acute and long-term cardiovascular effects of coffee, and its major constituents, which could underlie such an associat

  19. Long-term effects of climate change on Europe's water resources

    NARCIS (Netherlands)

    Domnisoru, A.

    2006-01-01

    Climate variations from last century show a global warming trend. Evidence from the past reveals that the anthropogenic greenhouse effect caused changes in climate parameters (temperature, precipitation and evaporation) at the European scale as well. On long-term this might have essential impact on

  20. Long-term effects of pediatric extracorporeal shockwave lithotripsy on renal function

    Directory of Open Access Journals (Sweden)

    Akin Y

    2014-04-01

    Full Text Available Yigit Akin,1 Selcuk Yucel21Department of Urology, Harran University School of Medicine, Sanliurfa, Turkey; 2Department of Urology, Acibadem University School of Medicine, Istanbul, TurkeyIntroduction: Extracorporeal shock wave lithotripsy (ESWL is a well-known and successful treatment modality. In addition, it can be used in premature infants. ESWL is used to treat kidney and ureter stones in children. However, although it is a preferred noninvasive treatment in that setting, there is debate about its long-term effects on growing kidneys in children.Objectives: To investigate the long-term effects of pediatric ESWL on renal function in light of updated literature.Methods: PubMed and Medline were searched for studies on ESWL in a pediatric population with keywords including efficacy, child, kidney calculi, ureter calculi, lithotripsy, injury, vascular trauma, and shock waves. The research was limited to the English literature during a period from 1980 to 2014. In total, 3,000 articles were evaluated, but only 151 papers were considered. Only the manuscripts directly related to the reviewed subjects were included in the current study.Results: However, the acute effects of ESWL in kidney are well-described. Although there are limited studies on the long-term effects of ESWL in children, there is a widespread opinion that ESWL is not affecting renal functions in the long-term.Conclusion: ESWL is a safe, effective, and noninvasive treatment option in children. Although ESWL can cause some acute effects in the kidney, there is no long-term effect on the growing kidneys of children.Keywords: child, lithotripsy, nephrolithiasis, renal injury, vascular trauma

  1. Computer simulation of microgravity long-term effects and risk evaluation

    Science.gov (United States)

    Perez-Poch, Antoni

    The objective of this work is to analyse and simulate possible long-term effects of microgravity on the human pulmonary function. It is also studied the efficacy of long-term regular exercise on relevant cardiovascular parameters when the human body is also exposed to microgravity. Little is known today about what long-term effects microgravity may cause on pulmonary function. It does not exist a complete explanation of the possible risks involved, although some experiments are under way on the ISS in order to evaluate them. Computer simulations are an important tool which may be used to predict and analyse these possible effects, and compare them with in-flight experiments. We based our study on a previous computer model (NELME: Numerical Evaluation of Long-term Microgravity Effects) which was developed in our laboratory and validated with the available data, focusing on the cardiovascular parameters affected by changes in gravity exposure. In this previous work we simulated part of the cardiovascular systems and we applied it to evaluate risks of blood-forming organs malfunction. NELME is based on an electrical-like control system model of the physiological changes, that may occur when gravity changes are applied. The computer implementation has a modular architecture. Hence, different output parameters, potential effects, organs and countermeasures can be easily implemented and evaluated. In this work we added a module to the system to analyse the pulmonary function with a gravity input parameter, as well as exposure time. We then conducted a battery of simulations when different values of g are applied for long-term exposures. We found no significant evidence of changes and no risks were foreseen. We also carried out an EVA simulation as a perturbation in the system (intense exercise, changes in breathed air) and studied the acute response. This is of great importance as current mission requirements do not allow data collection immediately following real EVAs

  2. Exploring the immediate and long-term impact on bacterial communities in soil amended with animal and urban organic waste fertilizers using pyrosequencing and screening for horizontal transfer of antibiotic resistance

    DEFF Research Database (Denmark)

    Riber, Leise; Poulsen, Pernille H. B.; Al-Soud, Waleed A.

    2014-01-01

    We investigated immediate and long-term effects on bacterial populations of soil amended with cattle manure, sewage sludge or municipal solid waste compost in an ongoing agricultural field trial. Soils were sampled in weeks 0, 3, 9 and 29 after fertilizer application. Pseudomonas isolates were...... time. Seasonal changes seemed to prevail with decreasing bacterial richness in week 9 followed by a significant increase in week 29 (springtime). The Pseudomonas population richness seemed temporarily affected by fertilizer treatments, especially in sludge- and compost-amended soils. To explain...

  3. Quality of life in Brazilian obese adolescents: effects of a long-term multidisciplinary lifestyle therapy

    Directory of Open Access Journals (Sweden)

    Tufik Sergio

    2009-07-01

    Full Text Available Abstract Background Obesity has adverse physical, social, and economic consequences that can negatively affect quality of life (QOL. Thus the aim of this study was to verify the effects of a long-term multidisciplinary lifestyle intervention on QOL, body image, anxiety, depression and binge eating in obese adolescents. Methods Sixty-six obese adolescents (41 girls and 25 boys; BMI: 35.62 ± 4.18 kg/m2 were recruited from the Multidisciplinary Obesity Intervention Program outpatient clinic, and were submitted to a multidisciplinary lifestyle therapy (short-term = 12 weeks and long-term = 24 weeks, composed of medical, dietary, exercise and psychological programs. Validated self-report questionnaires were used to assess symptoms of anxiety Trait/State (STAI; depression (BDI; binge eating (BES, body image dissatisfaction (BSQ and QOL (SF-36. Data were analyzed by means of scores; comparisons were made by ANOVA for repeated measures, and Tukey's test as post-hoc and Students T test. Results Long-term therapy decreased depression and binge eating symptoms, body image dissatisfaction, and improved QOL in girls, whereas, for boys, 24 weeks, were effective to reduce anxiety trait/state and symptoms of binge eating, and to improve means of dimensions of QOL (p Conclusion A long-term multidisciplinary lifestyle therapy is effective to control psychological aspects and to improve QOL in obese adolescents.

  4. Long-Term Effects of Untreated Adolescent Idiopathic Scoliosis: A Review of the Literature

    Science.gov (United States)

    Karavidas, Nikos; Moramarco, Marc; Moramarco, Kathryn

    2016-01-01

    Currently, adolescent idiopathic scoliosis (AIS) is principally regarded as benign, but some researchers have cited serious or extreme effects, including severe pain, cardiopulmonary compromise, social isolation, and even early death. Therefore, exploration of the long-term effects of AIS, the most common type of idiopathic scoliosis, is warranted. The purpose of this review was to examine the long-term studies on the natural history of AIS and/or reviews concerning the long-term effects of untreated AIS. A PubMed search was conducted using the key words idiopathic scoliosis, long-term effects and idiopathic scoliosis, natural history. For further analysis, references cited in those studies were reviewed for additional, related evidence not retrieved in the initial PubMed search. A review of the pertinent bibliography showed that older natural history studies did not distinguish between late-onset scoliosis (referred to in this paper as AIS) and early-onset scoliosis (EOS). The more recent studies offer such important distinction and reach to the general conclusion that untreated AIS does not lead to severe consequences with respect to signs and symptoms of scoliosis. It is possible that earlier studies may have included patient populations with EOS, leading to the perception of untreated scoliosis as having an unusually high morbidity rate. Studies on the long-term effects of AIS that specifically excluded EOS patients conclude that AIS is a benign disorder. This indicates that for research and reporting purposes, it is important to distinguishing between AIS and EOS. This will allow the practitioner and patient and their families to decide on an optimal treatment plan based on the most appropriate prognosis. PMID:27994795

  5. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing.

    Science.gov (United States)

    Ding, Long-Jun; Su, Jian-Qiang; Xu, Hui-Juan; Jia, Zhong-Jun; Zhu, Yong-Guan

    2015-03-01

    Iron reduction is an important biogeochemical process in paddy soils, yet little is known about the microbial coupling between nitrogen and iron reduction. Here, we investigated the shift of acetate-metabolizing iron-reducers under long-term nitrogen fertilization using (13)C-acetate-based ribosomal RNA (rRNA)-stable isotope probing (SIP) and pyrosequencing in an incubation experiment, and the shift of putative iron-reducers in original field samples were investigated by 16S rRNA gene-based pyrosequencing. During SIP incubations, in the presence of iron(III) oxyhydroxides, more iron(II) formation and less methane production were detected in nitrogen-fertilized (N) compared with non-fertilized (NF) soil. In (13)C-rRNA from microcosms amended with ferrihydrite (FER), Geobacter spp. were the important active iron-reducers in both soils, and labeled to a greater extent in N (31% of the bacterial classified sequences) than NF soils (11%). Pyrosequencing of the total 16S rRNA transcripts from microcosms at the whole community level further revealed hitherto unknown metabolisms of potential FER reduction by microorganisms including Pseudomonas and Solibacillus spp. in N soil, Dechloromonas, Clostridium, Bacillus and Solibacillus spp. in NF soil. Goethite (GOE) amendment stimulated Geobacter spp. to a lesser extent in both soils compared with FER treatment. Pseudomonas spp. in the N soil and Clostridium spp. in the NF soil may also be involved in GOE reduction. Pyrosequencing results from field samples showed that Geobacter spp. were the most abundant putative iron-reducers in both soils, and significantly stimulated by long-term nitrogen fertilization. Overall, for the first time, we demonstrate that long-term nitrogen fertilization promotes iron(III) reduction and modulates iron-reducing bacterial community in paddy soils.

  6. Effects of trawl selectivity and genetic parameters on fish body length under long-term trawling

    Science.gov (United States)

    Yu, Yang; Sun, Peng; Cui, He; Sheng, Huaxiang; Zhao, Fenfang; Tang, Yanli; Chen, Zelin

    2015-10-01

    Long-term fishing pressure affects the biological characteristics of exploited fish stocks. The biological characteristics of hairtail ( Trichiurus lepturus) in the East China Sea are unable to recover because of long-term trawling. Fishing induces evolutionary effects on the fish's biological characteristics. Evidence of these changes includes small size at age, a shift to earlier age structure, and early maturation. Natural and artificial selection usually affect the fish's life history. Selection can induce different chances of reproduction, and individual fish can give a different genetic contribution to the next generation. In this study, analysis of time-dependent probability of significance and test of sensitivity were used to explore the effects of fish exploitation rate, mesh size, and heritability with long-term trawling. Results showed that fishing parameters were important drivers to exploited fish population. However, genetic traits altered by fishing were slow, and the changes in biological characteristics were weaker than those caused by fishing selection. Exploitation rate and mesh size exhibited similar evolutionary trend tendency under long-term fishing. The time-dependent probability of significance trend showed a gradual growth and tended to be stable. Therefore, the direction of fishing-induced evolution and successful management of fish species require considerable attention to contribute to sustainable fisheries in China.

  7. Long-term complications and side effects of bariatric surgery: a systematic review

    Directory of Open Access Journals (Sweden)

    Alfonso Enrique Martínez-Núñez

    2017-09-01

    Full Text Available Background and objective: Bariatric surgery is a procedure that has gained popularity in the last decades as a treatment for obesity and is generally regarded as safe and effective in the short term, though the complications on the long term have been poorly described. We aim to review studies with long term follow-up reporting complications after a bariatric procedure. Method: A search was conducted on the data bases MEDLINE, EBSCO, Cochrane Library, and Google Scholar, and also scanning through references list in publications. We included cohort studies and clinical trials published from January 1st 2014 to April 15th 2017 with a follow up ≥ 5 years, retention rate above 50%, written in the following languages; English, Spanish, or Portuguese. We conducted qualitative bias assessment and analysis of heterogeneity. Result: Only four studies met the inclusion criteria, all of them were conducted with different bariatric procedures (vertical sleeve gastrectomy, laparoscopic sleeve gastrectomy, laparoscopic adjustable gastric banding, and billiopancreatic diversion with or without duodenal shift. Study design, outcome assessment, and complication definition were highly heterogeneous. The most frequent long term complications were gastroesophageal reflux disease, several nutritional deficits, incisional hernias, and failure to weight loss. Conclusions: There is insufficient evidence to ensure the quantity and severity of long-term complications of bariatric surgery.

  8. Effects of Different Long-term Fertilizer Managements on Microbial Biomass Carbon, Microbial Biomass Nitrogen and Microbial Quotient in Paddy Soil during Barley Growth Periods%长期施肥对大麦生育期双季稻田土壤微生物生物量碳、氮和微生物商的影响

    Institute of Scientific and Technical Information of China (English)

    唐海明; 郭立君; 肖小平; 汤文光; 孙继民; 汪柯; 李微艳

    2015-01-01

    Fertilizer inputs is the most important agricultural management practice affecting soil carbon and nitrogen content. Moreover, soil carbon and nitrogen provide a direct source for soil organisms. In China, only few studies have been conducted on the influence of long-term fertilizer and organic matter with fertilizer application on the soil microbiological properties. Our objective was to explore the characteristics of soil microbial biomass carbon (w(SMBC)), soil microbial biomass nitrogen (w(SMBN)) and soil microbial quotient in paddy soil during barley (Hordaum vulgare L.) growth periods with different long−term fertilizer managements in the double cropping rice system, we analyzed thew(SMBC),w(SMBN), soil microbial quotient and grain yield of barley by using mineral fertilizer alone (MF), rice residues plus mineral fertilizer (RF), 30% organic matter and 70% mineral fertilizer (OM1), 60% organic matter and 40% mineral fertilizer (OM2), and without fertilizer (CK). The long-term experiment was set up in 1986 in Ningxiang county, Hunan province, China. The results showed that different fertilization managements on paddy soil over the 28 years significantly affected soil chemical and microbial properties. That is, thew(SMBC),w(SMBN) and soil microbial quotient in paddy soil were increased by long-term fertilizer managements during barley growth periods. Meanwhile, thew(SMBC),w(SMBN) and soil microbial quotient reached the maximum at heading stage of barley. The activities ofw(SMBC) were increased by 20.04%, 26.47%, 45.94% and 51.42% with MF, RF, OM1 and OM2 at heading stage of barley, and the activities ofw(SMBN) were increased by 12.87%, 18.42%, 32.16 % and 36.55% with MF, RF, OM1 and OM2 at heading stage of barley compared with the CK, respectively. Furthermore, thew(SMBC),w(SMBN) and soil microbial quotient with OM1 and OM2 was significantly higher than that of MF, RF, CK at the main growth stages of barley. And thew(SMBC),w(SMBN) and soil microbial quotient

  9. Characterizing differences in the phosphorus activation coefficient of three typical cropland soils and the influencing factors under long-term fertilization.

    Science.gov (United States)

    Wu, Qihua; Zhang, Shuxiang; Zhu, Ping; Huang, Shaomin; Wang, Boren; Zhao, LinPing; Xu, Minggang

    2017-01-01

    The phosphorus activation coefficient (PAC, the ratio of available P to total P) is an important indicator of soil P availability and the transformation of P fractions. Understanding the details of the PAC is useful to estimate soil available P status and to provide P management guidance. In this research, soils from five long-term (23 years) fertilization treatments in three croplands were selected to examine the relationships between the PAC and P fractions and to analyse the influencing factors. PAC was affected by both soil types and fertilization treatments. Compared to the unfertilized control (CK) treatment, long-term P application significantly increased the PAC, all of the inorganic P (Pi) fractions and most of the organic P (Po) fractions in all the three soils, particularly in chemical fertilizer combined with manure treatment (NPKM). The PAC was significantly correlated to all of the Pi fractions proportions (Pvariance partitioning analysis showed that more variance of PAC is explained by soil factors (29.53%) than by P input (0.19%) and climate (0.25%) factors. Our findings demonstrate that P application increased the PAC by changing the Co content and the proportion of P fractions. Moreover, soil factors were the most important drivers of P transformations, and NPKM was optimal for improving soil fertility in Chinese croplands.

  10. Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion.

    Science.gov (United States)

    Xun, Weibing; Xu, Zhihui; Li, Wei; Ren, Yi; Huang, Ting; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-09-01

    Natural ecosystems comprise the planet's wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used high-throughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

  11. Arbuscular mycorrhizal fungus enhances P acquisition of wheat (Triticum aestivum L.) in a sandy loam soil with long-term inorganic fertilization regime.

    Science.gov (United States)

    Hu, Junli; Lin, Xiangui; Wang, Junhua; Cui, Xiangchao; Dai, Jue; Chu, Haiyan; Zhang, Jiabao

    2010-10-01

    The P efficiency, crop yield, and response of wheat to arbuscular mycorrhizal fungus (AMF) Glomus caledonium were tested in an experimental field with long-term (19 years) fertilizer management. The experiment included five fertilizer treatments: organic amendment (OA), half organic amendment plus half mineral fertilizer (1/2 OM), mineral fertilizer NPK, mineral fertilizer NK, and the control (without fertilization). AMF inoculation responsiveness (MIR) of wheat plants at acquiring P were estimated by comparing plants grown in unsterilized soil inoculated with G. caledonium and in untreated soil containing indigenous AMF. Without AMF inoculation, higher crop yields but lower colonization rates were observed in the NPK and two OA-inputted treatments, and NPK had significantly (P soils and thereby P acquisition of wheat plants compared with OA and 1/2 OM. G. caledonium inoculation significantly (P soil alkaline phosphatase (ALP) activity, only with the NPK treatment. This gave an MIR of ca. 45% on total P acquisition of wheat plants. There were no other remarkable MIRs. It suggested that the MIR is determined by soil available P status, and rational combination of AMF with chemical NPK fertilizer can compensate for organic amendments by improving P-acquisition efficiency in arable soils.

  12. Long-term incorporation of manure with chemical fertilizers reduced total nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Duan, Yinghua; Xu, Minggang; Gao, Suduan; Liu, Hua; Huang, Shaomin; Wang, Boren

    2016-09-01

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization are essential for sustainable agriculture. Quantifying the contribution of various fertilization regimes to soil N storage and loss has been lacking in a wide range of spatiotemporal scales. Based on data collected from field experiments at three typical agricultural zones in China, soil N dynamics and N changes in soil profile (0–100 cm) were examined during 1990–2009 under chemical fertilization, manure incorporation with fertilizer, and fertilizer with straw return treatments. We employed a mass balance approach to estimate the N loss to the environment after taking into account soil N change. Results showed a significant increase in soil N storage under manure incorporation treatments, accompanied with the lowest N loss (ave.20–24% of total N input) compared to all other treatments (ave.35–63%). Both soil N distribution and mass balance data suggested higher leaching risk from chemical fertilization in acidic soil of southern China with higher precipitation than the other two sites. This research concludes that manure incorporation with chemical fertilizer not only can achieve high N use efficiency and improve soil fertility, but also leads to the lowest total N loss or damage to the environment.

  13. Long-term incorporation of manure with chemical fertilizers reduced total nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Duan, Yinghua; Xu, Minggang; Gao, Suduan; Liu, Hua; Huang, Shaomin; Wang, Boren

    2016-01-01

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization are essential for sustainable agriculture. Quantifying the contribution of various fertilization regimes to soil N storage and loss has been lacking in a wide range of spatiotemporal scales. Based on data collected from field experiments at three typical agricultural zones in China, soil N dynamics and N changes in soil profile (0–100 cm) were examined during 1990–2009 under chemical fertilization, manure incorporation with fertilizer, and fertilizer with straw return treatments. We employed a mass balance approach to estimate the N loss to the environment after taking into account soil N change. Results showed a significant increase in soil N storage under manure incorporation treatments, accompanied with the lowest N loss (ave.20–24% of total N input) compared to all other treatments (ave.35–63%). Both soil N distribution and mass balance data suggested higher leaching risk from chemical fertilization in acidic soil of southern China with higher precipitation than the other two sites. This research concludes that manure incorporation with chemical fertilizer not only can achieve high N use efficiency and improve soil fertility, but also leads to the lowest total N loss or damage to the environment. PMID:27650801

  14. Effects of long-term fertilization on soil water and nutrient with Triticum aestivum L.succession in dryland of Loess Plateau%黄土旱塬长期施肥对小麦连作土壤养分和水分的影响

    Institute of Scientific and Technical Information of China (English)

    危锋; 郝明德

    2011-01-01

    To provide reference for reasonable use of water and fertilizer resources in dry-land of Loess Plateau,the study on the change of soil nutrient and water was conducted under the condition of 22-year Triticum aestivum L. succession based on the long-term fertilizer experiment. The six treatments were no fertilizer (CK) , nitrogen fertilizer (N) , phosphate fertilizer (P) , manure fertilizer (M) , nitrogen and phosphate fertilizers ( NP) , nitrogen and phosphate fertilizers with manure ( NPM ). Nutrient in tilth soils (0 -20 cm) , and water contents and water storage in soil profiles (0 -300 cm) were measured. The results showed that for the contents of soil organic matter, total N, total P, available N, available P, and available K in tilth soils, they increased by 55.44% , 45.24% , 29.63% , 67. 16% , 186.96% and 123.65% , respectively, after long-time M application. For contents of soil organ matter, total N, total P, available N, available P, and available K in tilth soils, they increased by 65.67% , 50.00% , 40. 74% , 72. 37% , 324. 58% and 191. 17% , respectively, after long-time NPM application. The water contents in tilth soils were 18. 19% , 17. 99% , 17. 66% , 17. 42% , 16. 96% and 16. 29% after longtime NPM, M, P, CK, N and NP treatments, respectively. The distribution characteristics of water contents in soil profile were similar for long-time NPM, M and NP treatments. The water storage of 0 - 300 cm soil layers were 666. 73, 656. 23, 629. 41, 536. 88, 504. 26 and 488. 47 mm in the P, CK, N, NP, M and NPM treatments, respectively. Compared to the CK, the wate storage in the P treatment increased by 1.60% , but decreased by 4.09% in the N treatment, 18. 19% in the NP treatment, 23. 16% in the M treatment and 25. 56% in the NPM treatment. The long-term application of single manure and chemical fertilizer combined with manure could increase nutrient and water contents in tilth soils. The water storage in 0 - 300 cm soil layers significantly decreased by the

  15. Forced migration in childhood: are there long-term health effects?

    Science.gov (United States)

    Saarela, Jan M; Elo, Irma T

    2016-12-01

    Studies on the health of migrants have increased considerably in number in recent years, but little is still known about the long-term health effects associated with forced migration, and particularly for people who were forced to migrate as children. Data shortcomings together with the methodological challenges of studying migrant populations limit the ability to disentangle the roles of various factors that influence migrant health outcomes. Finland provides an unusual opportunity to study long-term health consequences associated with forced migration. During World War II, twelve per cent of the Finnish population was forced to leave the region nowadays referred to as Ceded Karelia. After the war, these Karelians could not return home because the area was relinquished to the Soviet Union. Using high quality, linked register-based data for the period 1988-2012, we investigate whether this forced migration had long-term health consequences for those who were forced to migrate as children. Comparison groups are non-displaced persons born on the adjacent side of the new border, and people born elsewhere in Finland. Health at ages 43-65 years is measured by receipt of sickness benefit, which is an indicator of short-term illness, and receipt of disability pension, which reflects long-term illness or permanent disability. All-cause and cause-specific mortality is analysed at ages 43-84 years. We find no support for the hypothesis that the traumatic event of being forced to migrate during childhood has long-term negative health consequences. The forced child migrants have lower odds for receipt of sickness benefit, and women also have lower odds for receipt of disability pension. The mortality results are largely driven by patterns specific for eastern-born populations of Finland. A likely reason behind the absence of negative health consequences is that these migrants seem to have integrated well into post-war Finnish society.

  16. Effects Of Very Intensive Forest Biomass Harvesting On Short And Long Term Site Productivity

    DEFF Research Database (Denmark)

    Clarke, Nicholas; Callesen, Ingeborg; Helmisaari, Heljä-Sisko

    2008-01-01

    of the nutrient export and to the soil nutrient release capability. We suggest distinction of sensitive and robust soils. Six case studies are used to exemplify the approach and illustrate the importance of deposition, harvesting and soil properties. The distinction of sites and the quantification of nutrient......Intensified forest biomass utilisation causes export of substantial amounts of nutrients from the forest ecosystem. Compared to conventional stems-only harvesting, the most intensive biomass sce nario causes increases in nutrient exports of up to 6-7 times whereas the biomass export increases only...... up to 2 times (Stupak et al. 2007a). High concentrations of nutrients in small branches, twigs, and leaves compared to stems are the main reason. The extensive export of nutrients related to intensive biomass extraction have for many years caused concern for the long-term fertility of the system...

  17. How does education change the relationship between fertility and age-dependency under environmental constraints? A long-term simulation exercise

    Directory of Open Access Journals (Sweden)

    Erich Striessnig

    2014-02-01

    Full Text Available Background: When asked what a desirable fertility level for populations might be, most politicians, journalists, and even social scientists would say it is around two children per woman, a level that has been labelled by demographers "replacement-level fertility." The reasons given for considering this level of fertility as something to aim at usually include maintaining the size of the labour force and stabilizing the old-age-dependency ratio. Objective: In this paper, we scrutinize this wide-spread view by introducing education in addition to age and sex as a further relevant source of observable population heterogeneity. We consider several criteria for assessing the long-term implications of alternative fertility levels and present numerical simulations with a view on minimizing the education-weighted total dependency ratio and complement this with the goal of reducing the amount of greenhouse gas emission in the context of climate change. Methods: We perform thousands of alternative simulations for different fertility levels (assumed to be constant over time starting from empirically given population structures and derive the rate of fertility which yields the lowest level of our education-weighted dependency ratio. We study the sensitivity of our results to different parameter values and choose to focus on the actual populations of Europe and China over the course of the 21st century. Results: The results show that when education is assumed to present a cost at young age and results in higher productivity during adult age, then the fertility rate that on the long run keeps dependency at a minimum turns out to lie well below replacement fertility both in Europe and in China under a set of plausible assumptions. The optimal fertility level falls even lower when climate change is factored in as well. Conclusions: We conclude that there is nothing magical or particularly desirable about replacement level fertility.

  18. Long-term effects of the antibacterial agent triclosan on marine periphyton communities.

    Science.gov (United States)

    Eriksson, K Martin; Johansson, C Henrik; Fihlman, Viktor; Grehn, Alexander; Sanli, Kemal; Andersson, Mats X; Blanck, Hans; Arrhenius, Åsa; Sircar, Triranta; Backhaus, Thomas

    2015-09-01

    Triclosan is a widely used antibacterial agent that has become a ubiquitous contaminant in freshwater, estuary, and marine environments. Concerns about potential adverse effects of triclosan have been described in several recent risk assessments. Its effects on freshwater microbial communities have been well studied, but studies addressing effects on marine microbial communities are scarce. In the present study, the authors describe short- and long-term effects of triclosan on marine periphyton (microbial biofilm) communities. Short-term effects on photosynthesis were estimated after 60 min to 210 min of exposure. Long-term effects on photosynthesis, chlorophyll a fluorescence, pigment content, community tolerance, and bacterial carbon utilization were studied after exposing periphyton for 17 d in flow-through microcosms to 0.316 nM to 10,000 nM triclosan. Results from the short-term studies show that triclosan is toxic to periphyton photosynthesis. Half maximal effective concentration (EC50) values of 1080 nM and 3000 nM were estimated using (14)CO2-incorporation and pulse amplitude modulation (PAM) fluorescence measurements, respectively. After long-term triclosan exposure in flow-through microcosms, photosynthesis estimated using PAM fluorometry was not inhibited by triclosan concentrations up to 1000 nM but instead increased with increasing triclosan concentration. Similarly, at exposure concentrations of 31.6 nM and higher, triclosan caused an increase in photosynthetic pigments. At 316 nM triclosan, the pigment amounts were increased by a factor of 1.4 to 1.9 compared with the control level. Pollution-induced community tolerance was observed for algae and cyanobacteria at 100 nM triclosan and higher. Despite the widespread use of triclosan as an antibacterial agent, the compound did not have any effects on bacterial carbon utilization after long-term exposure.

  19. Long-term effects of a climate change teaching campaign – a case study

    DEFF Research Database (Denmark)

    Cruys-Bagger, Søren Ib; Daugbjerg, Peer

    2008-01-01

    The authors perform in association with School of Education, Aarhus University an evaluation of the long term effects of the campaign visit. We are investigating the sustainable effect of science campaigns for schools by collecting teachers reflection on the value of the visit of “Klimakaravanen...... of doing experiments c) Relations to technological companies and the civil society d) Skills of planning, performing and evaluating teaching...

  20. Effects of long-term grazing on sediment deposition and salt-marsh accretion rates

    OpenAIRE

    Elschot, K.; Bouma, T.J.; Temmerman, S.; J. P. Bakker

    2013-01-01

    Many studies have attempted to predict whether coastal marshes will be able to keep up with future acceleration of sea-level rise by estimating marsh accretion rates. However, there are few studies focussing on the long-term effects of herbivores on vegetation structure and subsequent effects on marsh accretion. Deposition of fine-grained, mineral sediment during tidal inundations, together with organic matter accumulation from the local vegetation, positively affects accretion rates of marsh...

  1. Long-term effects of interference on short-term memory performance in the rat.

    Science.gov (United States)

    Missaire, Mégane; Fraize, Nicolas; Joseph, Mickaël Antoine; Hamieh, Al Mahdy; Parmentier, Régis; Marighetto, Aline; Salin, Paul Antoine; Malleret, Gaël

    2017-01-01

    A distinction has always been made between long-term and short-term memory (also now called working memory, WM). The obvious difference between these two kinds of memory concerns the duration of information storage: information is supposedly transiently stored in WM while it is considered durably consolidated into long-term memory. It is well acknowledged that the content of WM is erased and reset after a short time, to prevent irrelevant information from proactively interfering with newly stored information. In the present study, we used typical WM radial maze tasks to question the brief lifespan of spatial WM content in rodents. Groups of rats were submitted to one of two different WM tasks in a radial maze: a WM task involving the repetitive presentation of a same pair of arms expected to induce a high level of proactive interference (PI) (HIWM task), or a task using a different pair in each trial expected to induce a low level of PI (LIWM task). Performance was effectively lower in the HIWM group than in LIWM in the final trial of each training session, indicative of a "within-session/short-term" PI effect. However, we also observed a different "between-session/long-term" PI effect between the two groups: while performance of LIWM trained rats remained stable over days, the performance of HIWM rats dropped after 10 days of training, and this impairment was visible from the very first trial of the day, hence not attributable to within-session PI. We also showed that a 24 hour-gap across training sessions known to allow consolidation processes to unfold, was a necessary and sufficient condition for the long-term PI effect to occur. These findings suggest that in the HIWM task, WM content was not entirely reset between training sessions and that, in specific conditions, WM content can outlast its purpose by being stored more permanently, generating a long-term deleterious effect of PI. The alternative explanation is that WM content could be transferred and stored

  2. Long-term impact of prevention programs to promote effective parenting: lasting effects but uncertain processes.

    Science.gov (United States)

    Sandler, Irwin N; Schoenfelder, Erin N; Wolchik, Sharlene A; MacKinnon, David P

    2011-01-01

    This article reviews findings from 46 randomized experimental trials of preventive parenting interventions. The findings of these trials provide evidence of effects to prevent a wide range of problem outcomes and to promote competencies from one to 20 years later. However, there is a paucity of evidence concerning the processes that account for program effects. Three alternative pathways are proposed as a framework for future research on the long-term effects of preventive parenting programs: (a) through program effects on parenting skills, perceptions of parental efficacy, and reduction in barriers to effective parenting; (b) through program-induced reductions in short-term problems of youth that persist over time, improvements in youth adaptation to stress, and improvements in youth belief systems concerning the self and their relationships with others; and (c) through effects on contexts in which youth become involved and on youth-environment transactions.

  3. Specific immunotherapy has long-term preventive effect of seasonal and perennial asthma

    DEFF Research Database (Denmark)

    Jacobsen, L; Niggemann, B; Dreborg, S;

    2007-01-01

    evaluated the long-term clinical effect and the preventive effect of developing asthma 7-years after termination of SIT. METHODS: One hundred and forty-seven subjects, aged 16-25 years with grass and/or birch pollen allergy was investigated 10 years after initiation of a 3-year course of SIT......BACKGROUND: 3-year subcutaneous specific immunotherapy (SIT) in children with seasonal allergic rhinoconjunctivitis reduced the risk of developing asthma during treatment and 2 years after discontinuation of SIT (5-year follow-up) indicating long-term preventive effect of SIT. OBJECTIVE: We...... with standardized allergen extracts of grass and/or birch or no SIT respectively. Conjunctival provocations were performed outside the season and methacholine bronchial provocations were performed during the season and winter. Asthma was assessed by clinical evaluation. RESULTS: The significant improvements...

  4. Factors associated with the effectiveness of continuing education in long-term care.

    Science.gov (United States)

    Stolee, Paul; Esbaugh, Jacquelin; Aylward, Sandra; Cathers, Tamzin; Harvey, David P; Hillier, Loretta M; Keat, Nancy; Feightner, John W

    2005-06-01

    This article examines factors within the long-term-care work environment that impact the effectiveness of continuing education. In Study 1, focus group interviews were conducted with staff and management from urban and rural long-term-care facilities in southwestern Ontario to identify their perceptions of the workplace factors that affect transfer of learning into practice. Thirty-five people were interviewed across six focus groups. In Study 2, a Delphi technique was used to refine our list of factors. Consensus was achieved in two survey rounds involving 30 and 27 participants, respectively. Management support was identified as the most important factor impacting the effectiveness of continuing education. Other factors included resources (staff, funding, space) and the need for ongoing expert support. Organizational support is necessary for continuing education programs to be effective and ongoing expert support is needed to enable and reinforce learning.

  5. Long-term effects of propolis on serum biochemical parameters of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Beyraghdar Kashkooli, Omid; Ebrahimi Dorcheh, Eisa; Mahboobi-Soofiani, Nasrollah; Samie, Abdolhossein

    2011-03-01

    Long-term effects of propolis administration on serum biochemical parameters of rainbow trout (Oncorhynchus mykiss) were investigated. To determine the possible toxicity and side effects of propolis, fish were fed on diets containing 0, 0.5, 1.5, 4.5 and 9 g propolis/kg diet for 8 weeks. At the end of the experiment, various seric biochemical parameters were determined. Our results showed that all dosages induced no significant alterations in growth parameters and the seric levels of total protein, albumin, globulin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides and activities of glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, alkaline phosphatase and lactate dehydrogenase, when compared to the control group. On the basis of our findings, propolis is a non-toxic substance for rainbow trout and its long-term administration might not have any side effects. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Long-Term Effect of TMD on Vibration Control of An MDOF Offshore Fixed Platform

    Institute of Scientific and Technical Information of China (English)

    SHI Xiang(石湘); Tetsuya MATSUI; WU Minger

    2003-01-01

    A three-dimensional fixed offshore platform in deep water modeled by the finite element method is studied in this paper. Analysis of the dynamic response of the MDOF structure is realized taking the non-linearity of the wave drag force and the wave-structure interaction into account. The structural response statistics, which have Gaussian distributions, are used to evaluate the vibration effect of the structure without TMD and with TMD. And an optimal method to design TMD controlling the first mode of the multi-mode structure is proposed. Moreover, the probabilities of occurrence of sea states at the platform site are considered for prediction of the long-term effect of a TMD. Simulation results demonstrate that the long-term effect of a well-designed TMD is good and the practical use is possible due to the good stability of its optimal parameters under different sea states.

  7. Long term effect of monosodium glutamate in liver of albino mice after neo-natal exposure.

    Science.gov (United States)

    Bhattacharya, T; Bhakta, A; Ghosh, S K

    2011-03-01

    Mono Sodium Glutamate (MSG) is a naturally occurring excitatory neurotransmitter. It is extensively used as a food additive and flavoring agent for its UMAMI taste. Simultaneously it is being implicated for varied pathological condition like obesity, gonadal dysfunction, learning difficulty etc. It produces oxygen derived free radicals and metabolized in liver. Neonate mice are sensitive and suffer from adverse effects. Present work was undertaken to study the long term effects on histology of liver following MSG injection in neonates. The changes in the liver parenchyma of 75 days old mice showed variable changes. Areas around central vein were most affected. The liver cords were disrupted, dilated sinusoids, prominent Kupffer cells with accumulation of particulate matter.There were inflammatory cells around central vein. The hepatocyte cell membrane were disrupted, cytoplasm vacuolated, nucleus were pyknotic. Even the normal looking cells showed depletion of PAS +ve material in the cytoplasm.The long term effect on histology showed moderate and patchy hepatocellular damage.

  8. Low frequency electromagnetic fields long-term exposure effects on testicular histology, sperm quality and testosterone levels of male rats

    Institute of Scientific and Technical Information of China (English)

    Aminollah Bahaodini; Maryam Owjfard; Amin Tamadon; Seyedeh Marzieh Jafari

    2015-01-01

    Objective:To evaluate the effects of long-term exposure to low frequency EMF on the testicular function and structure.Methods:Fourteen adult male rats were randomly and equally divided into sham and experimental groups. Experimental group was exposed to 1 mT, 50 Hz EMF, continuously for 85 days in a solenoid. Sham group was kept under conditions same as experimental group, without EMF. At the end of the exposure period, weight and size of testes, sperm evaluation (sperm counts, motility and viability), histological testicular sections and serum total testosterone were determined.Results:Long-term exposure to low frequency EMF significantly decreased the diameter of the seminiferous tubules and increased number of seminiferous tubules per unit area of testes. In addition, low frequency EMF significantly reduced sperm motility and testosterone levels. However, it had no effect on the weight and size of testes, sperm concentration, and viability. Conclusion:Prolonged exposure to 50 Hz EMF has an adverse effect on male fertility.

  9. Long-term cognitive and academic effects of early childhood education on children in poverty.

    Science.gov (United States)

    Barnett, W S

    1998-01-01

    It is generally accepted that early childhood education improves the cognitive performance of children in poverty in the short-term, but whether cognitive effects persist in the long-term is hotly debated. This paper presents the results of a critical review of 38 studies of the long-term effects of early childhood programs on children in poverty. Outcomes examined include IQ, achievement, and academic success as measured by grade repetition, special education placement, and high school graduation. Early childhood education is found to produce persistent effects on achievement and academic success, but not on IQ (with some exceptions). Head Start and public school programs produce the same types of effects as better funded model programs, but at least some of the effects are smaller. Cost-benefit analysis based on one randomized trial finds that the economic return from providing early education to children in poverty far exceeds the costs. Head Start, public school preschool education, and education in high-quality child care programs all offer avenues for government investment to improve the long-term cognitive development and academic success of children in poverty.

  10. Acute and long-term in vitro effects of zinc oxide nanoparticles.

    Science.gov (United States)

    Annangi, Balasubramanyam; Rubio, Laura; Alaraby, Mohamed; Bach, Jordi; Marcos, Ricard; Hernández, Alba

    2016-09-01

    Since most of the toxic studies of zinc oxide nanoparticles (ZnO NPs) focused on acute and high-dose exposure conditions, the aim of the present study was to fill the existing knowledge gap of long-term effects of ZnO NPs at sub-toxic doses. To overcome this point, we have evaluated the toxic, genotoxic, and carcinogenic effects of ZnO NPs under long-term treatments (12 weeks), using a sub-toxic dose (1 µg/mL) according to acute 48-h exposure. Preliminarily, oxidative stress and genotoxic/oxidative DNA damage were determined under acute exposure and high-dose conditions. To determine the role of oxidative DNA damage, a wild-type mouse embryonic fibroblast (MEF Ogg1 (+/+)) and its isogenic 8-oxo-guanine DNA glycosylase 1 (Ogg1) knockout partner (MEF Ogg1 (-/-)) cell lines were used. Although short-term exposure (24-h) experiments demonstrated that ZnO NPs were able to induce ROS, genotoxicity, and oxidative DNA damage in both cell lines, no effects were obtained under long-term exposure scenario. Thus, 1 µg/mL exposure over 12 weeks was unable to induce genotoxicity as well as cellular transformation in both cell types, as indicated by the lack of observed morphological cell changes, variations in the secretion of matrix metalloproteinases, and anchorage-independent cell growth ability, regarded as cancer-like phenotypic hallmarks. Our results indicate that short-term effects of ZnO NP exposure are not replicated under long-term and sub-toxic dose conditions. All together, the lack of genotoxic/carcinogenic effects after chronic treatments seem to indicate a reduced risk associated with ZnO NP exposure.

  11. Long-term versus short-term warming effects on microbial processes

    Science.gov (United States)

    Walker, Tom; Leblans, Niki; Sigurdsson, Bjarni D.; Richter, Andreas

    2016-04-01

    Rapid warming in high latitude ecosystems is predicted to drive massive losses of carbon dioxide (CO2) from soils to the atmosphere, raising concerns that it will create a positive feedback to climate change. However, such predictions expect that temperature effects on soil microbes, as chief producers of CO2, will persist over time scales meaningful to the climate system (i.e. decades to centuries). There is increasing awareness that the soil microbial community can acclimate to temperature change over time scales from months to years, resulting in attenuating responses of CO2 release to the atmosphere. Despite this, nothing is currently known about long-term warming effects on the activity or physiology of high latitude soil microbes, and, through this, the longevity of CO2 losses from these ecosystems. We conducted a study at a unique research site that makes use of natural (geothermal) gradients in soil temperature that have been in place for over 35 years as a natural warming treatment. We determined long-term warming effects (+0.5 °C, +1.5 °C, +3 °C and +6 °C) on soil CO2 release through microbial respiration in a laboratory incubation experiment, and explored microbial carbon use efficiency and soil carbon and nitrogen pools as mechanisms. We also performed a companion experiment to compare long-term warming effects on microbial processes to those caused by six weeks of warming of ambient soil to +3 °C and +6 °C. We show that while six weeks of warming consistently increased microbial respiration by up to 30%, this effect did not persist in soils exposed to 35 years of warming. We present further data linking such long-term thermal acclimation to shifts in microbial carbon use efficiency and soil carbon and nitrogen availability, and discuss our findings in the context of warming-driven feedbacks from high latitude soils to future climate change.

  12. Effect of the Danish return-to-work program on long-term sickness absence

    DEFF Research Database (Denmark)

    Poulsen, Otto M; Aust, Birgit; Bjørner, Jakob

    2014-01-01

    participant receiving ordinary sickness benefit management (OSM). Study participants were working-age adults receiving long-term (≥8 weeks or more) benefits, included regardless of reason for sickness absence or employment status. Each beneficiary was followed-up for a maximum period of 52 weeks. Cox......OBJECTIVES: The aim of this study was to evaluate the effect of the Danish return-to-work (RTW) program on long-term sickness absence in a randomized controlled trial in three municipalities. METHODS: The intervention group comprised 1948 participants while the control group comprised 1157...... proportional hazards model was used to estimate hazard ratios (HR) for return to work (RTW) with 95% confidence intervals (95% CI). RESULTS: The intervention effect differed significantly between the municipalities (P=0.00005). In one municipality (M2) the intervention resulted in a statistically significant...

  13. Comparative analysis of two community stressors' long-term mental health effects

    Energy Technology Data Exchange (ETDEWEB)

    Dew, M.A.; Bromet, E.J.; Schulberg, H.C.

    1987-04-01

    The investigation directly compared the long-term mental health consequences of two community-wide stressors, the Three Mile Island (TMI) nuclear accident and widespread unemployment due to layoff, in demographically comparable samples of women. Results showed a marked degree of similarity in the stressors' effects: Levels of subclinical symptomatology were elevated to similar degrees in each sample during the year following stressor onset, and symptom levels remained elevated in each sample 2 to 3 1/2 years later. Moreover, variables identified as predictors of enduring psychological distress were virtually identical for the two samples. Additional analyses revealed that the mental health status of unemployed husbands mediated the negative psychological effects of layoff on their wives. Implications of these results for understanding the long-term consequences of exposure to community-wide stress are discussed.

  14. The effects, limitations, and long-term dentofacial adaptations to treatment with the Herbst appliance.

    Science.gov (United States)

    Pancherz, H

    1997-12-01

    The purpose of this article is to summarize the existing scientific data with respect to the short- and long-term effects of the Herbst appliance on the occlusion and on the maxillo/mandibular complex. The article also discusses the treatment indications and possible treatment limitations. The Herbst method is most effective in the treatment of Class II malocclusions. Long-term stability seems to be dependent on a stable cuspal interdigitation. Marked mandibular morphological changes occur during therapy and sagittal condylar growth is increased. Posttreatment, most of the mandibular morphological changes revert and no long-term influence of Herbst treatment on mandibular growth can be verified. The appliance effect on the maxillary complex can be compared with that of a high-pull headgear. Without proper retention, however, this effect is of a temporary nature. Herbst treatment is especially indicated in the permanent dentition at or just after the pubertal peak of growth. Mixed dentition treatment is not recommended, as a stable cuspal interdigitation after therapy is difficult to achieve and relapses are prone to occur. In the nongrowing patient, the appliance should be used with great caution.

  15. Long-Term Effects of Recommendation on the Evolution of Online Systems

    Science.gov (United States)

    Zhao, Dan-Dan; Zeng, An; Shang, Ming-Sheng; Gao, Jian

    2013-11-01

    We employ a bipartite network to describe an online commercial system. Instead of investigating accuracy and diversity in each recommendation, we focus on studying the influence of recommendation on the evolution of the online bipartite network. The analysis is based on two benchmark datasets and several well-known recommendation algorithms. The structure properties investigated include item degree heterogeneity, clustering coefficient and degree correlation. This work highlights the importance of studying the effects and performance of recommendation in long-term evolution.

  16. LONG TERM EFFECT OF CYRIAX PHYSIOTHERPY WITH SUPERVISED EXERCISE PROGRAM IN SUBJECTS WITH TENNIS ELBOW

    OpenAIRE

    Pallavi Shridhar Thakare; Vinod Babu. K; Sai Kumar. N; Ayyappan. V.R

    2014-01-01

    Background: The purpose is to find long term effect of Cyriax physiotherapy with supervised exercise program in the reduction of pain and improvement of functional ability for subjects with tennis elbow. Method: An experimental study design, 30 subjects with Tennis Elbow randomized 15 subjects each into Study and Control group. Control group received Supervised Exercise program while Study group received Cyriax Physiotherapy with Supervised exercises program thrice in a week for 4 weeks an...

  17. Physical activity and late effects in childhood acute lymphoblastic leukemia long-term survivors.

    Science.gov (United States)

    Bertorello, N; Manicone, R; Galletto, C; Barisone, E; Fagioli, F

    2011-08-01

    In the present study the authors evaluated therapy-related long-term adverse effects and physical activity in a cohort of long-term survivors of childhood acute lymphoblastic leukemia (ALL), diagnosed in their center between March 1991 and August 2000, treated according to the AIEOP (Associazione Italiana di Ematologia e Oncologia Pediatrica) ALL 91 or 95 study protocol and regularly seen in the authors' long-term follow-up unit. The authors analyzed the long-term sequelae of major body systems in this cohort of subjects and administered an "ad hoc" questionnaire concerning sport. The authors found that 70 patients out of 102 (68.5%) showed no late effects, 10% presented only instrumental or neuropsychological test abnormalities, and 21.5% had 1 or more clinical late sequelae. None of the evidenced late effects represented a contraindication to do physical activity. Sixty-one percent of survivors do physical activity, most of them regularly. Sixty-one percent of males and 18.5% of females (P < .005) do competitive sport (sports rates are similar to those of the general age-matched population). Nearly all subjects spontaneously choose to do sport and think physical exercise is an important and useful resource for their health. The authors conclude that the more recent therapy regimens for leukemia treatment, excluding bone marrow transplantation, do not seem to cause such late effects as to prevent survivors from doing sport. Therefore, in the care of ALL survivors, physical activity is not only not contraindicated, but should also be promoted as much as possible. The development of specific educational programs is warranted as part of the care of cancer survivors.

  18. Effects of Long-term Exposure to Hydrogen Sulfide on Human Red Blood Cells

    Directory of Open Access Journals (Sweden)

    A Saeedi

    2015-01-01

    Full Text Available Background: Hydrogen sulfide (H2S exhibits both physiological and toxicological roles in the biological systems. Acute exposure to high levels of H2S is life threatening while long-term exposure to ambient levels of H2S elicits human health effects. Objective: To study the harmful effects of long-term exposure to low levels of H2S on human blood cells. Methods: 110 adult workers from Iran who were occupationally exposed to 0–90 ppb H2S for 1–30 years were studied. The participants aged between 18 and 60 years and were exposed directly or indirectly to sulfur compounds (exposed group. The origin of H2S was natural gas processing plants. A control group consisting of 110 males who were not in contact with H2S was also studied. For all participants, hematological profile including total hemoglobin and red blood cell count and sulfhemoglobin, methemoglobin levels were measured. Results: Among all parameters evaluated in this study the mean methemoglobin and sulfhemoglobin levels were significantly higher among workers who were exposed to sulfur compounds than the control group. Major differences throughout the study period for sulfhemoglobinemia among exposed groups were observed. Conclusion: Long-term exposure to even low levels of H2S in workplaces may have potential harmful effects on human health.

  19. [The effect of long-term lithium treatment on kidney function].

    Science.gov (United States)

    Rybakowski, Janusz; Drogowska, Joanna; Abramowicz, Maria; Chłopocka-Woźniak, Maria; Czekalski, Stanisław

    2012-01-01

    In 1963 it was first demonstrated that long-term lithium administration exerts a "mood-stabilising" effect, preventing recurrences of mania and depression in bipolar affective disorder. Despite the introduction of many other drugs having mood-stabilising effect, lithium still remains the first choice drug for the prophylaxis of affective episodes in mood disorder. Lithium is eliminated nearly exclusively by the kidneys: lithium clearance is proportional to creatinine clearance and is influenced by natriuretic and antinatriuretic factors. Nowadays, nearly 40-year experience with long-term lithium treatment point to a possibility of nephrotoxic effects of this ion. Impaired urinary concentrating ability, which, in a few patients can reach an intensity of diabetes insipidus, can occur after several weeks of lithium administration. Favourable results in the treatment of diabetes insipidus have been obtained with amiloride, the drug which block epithelial sodium channel. However, after 10-20 years of treatment, lithium-induced interstitial nephropathy may be demonstrated in some patients, which, in small proportion of the latter may lead to end-stage renal disease. Lithium-induced hipercalcemia and nephrotic syndrome are rare complications of lithium therapy. In patients on long-term lithium therapy periodic monitoring of kidney function by measuring serum creatinine concentration and glomerular filtration rate is necessary. In case of detecting nephropathy, a discontinuation of lithium sho uld be considered. The patient in whom lithium was discontinued due to nephropathy should remain in nephrological treatment.

  20. Effects of long-term corset wearing on chronic low back pain.

    Science.gov (United States)

    Sato, Naoto; Sekiguchi, Miho; Kikuchi, Shinichi; Shishido, Hiroaki; Sato, Katsuhiko; Konno, Shinichi

    2012-01-01

    There are few studies of the therapeutic effects of long-term corset wearing in patients with chronic low back pain. The aim of this study was to evaluate the effects of long-term corset wearing on chronic low back pain and to examine the myoelectrical activities of the paravertebral muscles. Forty subjects with chronic low back pain were enrolled and randomly divided into two groups: a group wearing corsets for 6 months (CW) group and a group not wearing corsets (NW). The treatment effects were measured using the Japanese Orthopaedic Association (JOA) score. Muscle endurance was evaluated during the Biering-Sorensen test (S-test), and the degree of muscle fatigue was evaluated by the change in percent mean power frequency (%MPF) of the paravertebral muscles. Corset treatment for chronic low back pain improved low back pain and increased muscle endurance for a short period of time. Paravertebral muscle fatigue was not increased by long-term corset wearing for chronic low back pain, and weakening of the paravertebral muscles was not observed up to 6 months after the start of corset wearing.

  1. New-onset postoperative atrial fibrillation after aortic valve replacement: Effect on long-term survival.

    Science.gov (United States)

    Swinkels, Ben M; de Mol, Bas A; Kelder, Johannes C; Vermeulen, Freddy E; Ten Berg, Jurriën M

    2017-08-01

    There is a paucity of data on long-term survival of new-onset postoperative atrial fibrillation (POAF) after cardiac surgery. Also, mean follow-up in previous studies is confined to a maximum of one decade. This retrospective, longitudinal cohort study was performed to determine the effect on long-term survival of new-onset POAF after aortic valve replacement (AVR) over a mean follow-up of almost 2 decades. Kaplan-Meier survival analysis was used to determine long-term survival after AVR, performed between January 1, 1990, and January 1, 1994, in 569 consecutive patients without a history of atrial fibrillation, divided into 241 patients (42.4%) with and 328 patients (57.6%) without new-onset POAF. New-onset POAF was considered in multivariable analysis for decreased long-term survival. After AVR, patients with new-onset POAF were treated with the aim to restore sinus rhythm within 24 to 48 hours from onset by medication and when medication failed by direct-current cardioversion before discharge home. Mean follow-up after AVR was 17.8 ± 1.9 years. Incidence of new-onset POAF was 42.4%. Kaplan-Meier overall cumulative survival rates at 15 years of follow-up were similar in the patients with new-onset POAF versus those without: 41.5% (95% confidence interval [CI], 35.2-47.7) versus 41.3% (95% CI, 36.0-46.7), respectively. New-onset POAF was not an independent risk factor for decreased long-term survival (hazard ratio 0.815; 95% CI, 0.663-1.001; P = .052). New-onset POAF after AVR does not affect long-term survival when treatment is aimed to restore sinus rhythm before discharge home. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  2. Long-term Effects of Nutrient Addition and Phytoremediation on Diesel and Crude Oil Contaminated Soils in subarctic Alaska.

    Science.gov (United States)

    Leewis, Mary-Cathrine; Reynolds, Charles M; Leigh, Mary Beth

    2013-12-01

    Phytoremediation is a potentially inexpensive method of detoxifying contaminated soils using plants and associated soil microorganisms. The remote locations and cold climate of Alaska provide unique challenges associated with phytoremediation such as finding effective plant species that can achieve successful site clean-up despite the extreme environmental conditions and with minimal site management. A long-term assessment of phytoremediation was performed which capitalized on a study established in Fairbanks in 1995. The original study sought to determine how the introduction of plants (Festuca rubra, Lolium multiflorum), nutrients (fertilizer), or their combination would affect degradation of petroleum hydrocarbon (TPH) contaminated soils (crude oil or diesel) over time. Within the year following initial treatments, the plots subjected to both planting and/or fertilization showed greater overall decreases in TPH concentrations in both the diesel and crude oil contaminated soils relative to untreated plots. We re-examined this field site after 15 years with no active site management to assess the long-term effects of phytoremediation on colonization by native and non-native plants, their rhizosphere microbial communities and on petroleum removal from soil. Native and non-native vegetation had extensively colonized the site, with more abundant vegetation found on the diesel contaminated soils than the more nutrient-poor, more coarse, and acidic crude oil contaminated soils. TPH concentrations achieved regulatory clean up levels in all treatment groups, with lower TPH concentrations correlating with higher amounts of woody vegetation (trees & shrubs). In addition, original treatment type has affected vegetation recruitment to each plot with woody vegetation and more native plants in unfertilized plots. Bacterial community structure also varies according to the originally applied treatments. This study suggests that initial treatment with native tree species in

  3. Long-term Effects of Nutrient Addition and Phytoremediation on Diesel and Crude Oil Contaminated Soils in subarctic Alaska

    Science.gov (United States)

    Leewis, Mary-Cathrine; Reynolds, Charles M.; Leigh, Mary Beth

    2014-01-01

    Phytoremediation is a potentially inexpensive method of detoxifying contaminated soils using plants and associated soil microorganisms. The remote locations and cold climate of Alaska provide unique challenges associated with phytoremediation such as finding effective plant species that can achieve successful site clean-up despite the extreme environmental conditions and with minimal site management. A long-term assessment of phytoremediation was performed which capitalized on a study established in Fairbanks in 1995. The original study sought to determine how the introduction of plants (Festuca rubra, Lolium multiflorum), nutrients (fertilizer), or their combination would affect degradation of petroleum hydrocarbon (TPH) contaminated soils (crude oil or diesel) over time. Within the year following initial treatments, the plots subjected to both planting and/or fertilization showed greater overall decreases in TPH concentrations in both the diesel and crude oil contaminated soils relative to untreated plots. We re-examined this field site after 15 years with no active site management to assess the long-term effects of phytoremediation on colonization by native and non-native plants, their rhizosphere microbial communities and on petroleum removal from soil. Native and non-native vegetation had extensively colonized the site, with more abundant vegetation found on the diesel contaminated soils than the more nutrient-poor, more coarse, and acidic crude oil contaminated soils. TPH concentrations achieved regulatory clean up levels in all treatment groups, with lower TPH concentrations correlating with higher amounts of woody vegetation (trees & shrubs). In addition, original treatment type has affected vegetation recruitment to each plot with woody vegetation and more native plants in unfertilized plots. Bacterial community structure also varies according to the originally applied treatments. This study suggests that initial treatment with native tree species in

  4. Effects of long-term high temperature exposure on the microstructure of Haynes alloy 230

    Energy Technology Data Exchange (ETDEWEB)

    Veverkova, J.; Strang, A.; Atkinson, H.V. [Leicester Univ. (United Kingdom). Dept. of Engineering; Marchant, G.R. [Siemens Industrial Turbomachinery Ltd., Lincoln (United Kingdom)

    2010-07-01

    Haynes Alloy 230 was specifically designed to have excellent long-term thermal stability and resistance to the precipitation of damaging phases. This paper describes in detail studies on the effects of long-term high temperature exposure on the hardness, microstructural changes and tensile properties of thermally exposed samples of Haynes Alloy 230. The samples from the 2mm thick sheet material have been investigated using X-Ray diffraction and advanced electron microscopy techniques (FEGSEM, TEM etc.). The evolution of the precipitating phases was monitored across a wide range of temperatures (from 500 C to 1170 C) and durations (from 24 hours up to 30000 hours) and several key phases have been identified. In addition to the primary W-rich carbide and the precipitation of Cr-rich M{sub 23}C{sub 6}, a new brittle phase/carbide was observed within the microstructure at the highest exposure temperatures (above 930 C). (orig.)

  5. Effect of long-term aluminum feeding on lipid/phospholipid profiles of rat brain myelin

    Directory of Open Access Journals (Sweden)

    Dave Kunjan R

    2004-06-01

    Full Text Available Abstract Effect of long-term (90–100 days exposure of rats to soluble salt of aluminum (AlCl3 on myelin lipid profile was examined. The long-term exposure to AlCl3 resulted in a 60 % decrease in the total phospholipid (TPL content while the cholesterol (CHL content increased by 55 %. Consequently the TPL / CHL molar ratio decreased significantly by 62 %. The phospholipid composition of the myelin membrane changed drastically; the proportion of practically all the phospholipid classes decreased by 32 to 60 % except for phosphatidylcholine (PC and phosphatidylethanolamine (PE. Of the latter two, proportion of PC was unchanged while PE increased in proportion by 47 %. Quantitatively, all phospholipid classes decreased by from 42 to 76% with no change in the PE content. However the membrane fluidity was not altered in Al-treated rats. Many of the changes we observe here show striking similarities with the reported phospholipid profiles of Alzheimer brains.

  6. Long-term effects of valproic acid on reproductive endocrine functions in Turkish women with epilepsy.

    Science.gov (United States)

    Gorkemli, Huseyin; Genc, Bulent Oguz; Dogan, Ebru Apaydin; Genc, Emine; Ozdemir, Suna

    2009-01-01

    The long-term effects of valproic acid (VPA) on reproductive endocrine functions in women with epilepsy (WWE) were studied. Serum reproductive hormone concentrations, clinical findings and ovarian morphology were analyzed in 71 WWE who had been receiving antiepileptic drugs (AED) for a minimum of 2 years. Of the 71 WWE, polycystic ovarian syndrome (PCOS) (p = 0.011) and menstrual irregularities (p = 0.009) were found to be more prevalent in women receiving VPA treatment when compared to women on non-VPA treatment. There was no statistically significant dose or duration-related rise of risk for patients who developed PCOS and menstrual irregularities and those who were not on long-term VPA therapy. The lack of a duration-related reproductive dysfunction in this patient population may support the hypothesis of early occurring VPA-associated metabolic and endocrine changes.

  7. Effects of crop rotation and reduced nitrogen fertilisation on Apera spica-venti populations in a long-term experiment.

    Science.gov (United States)

    Schulz, A; Pallurt, B; Gerowitt, B

    2011-01-01

    Apera spica-venti is one of the most serious annual grass weeds in Germany and may cause considerably yield losses in untreated fields. A long-term field experiment was conducted investigating the effects of crop rotation and nitrogen fertiliser use on A. spica-venti populations. A six-field cash-crop rotation with 67% winter cereals and a six-field fodder crop rotation with 50% winter cereals were studied. The rate of tillering was in the fodder crop rotation significantly higher than in the cash crop rotation. The halving of nitrogen fertilizer dose caused a significant increase in the tillering rate. Most plants of A. spica-venti emerged in winter wheat. There was an increase of emerged A. spica-venti in winter wheat from year to year.

  8. Effects of long-term warming and fertilisation on microarthropod abundances in three sub-arctic ecosystems

    DEFF Research Database (Denmark)

    Sjursen, Heidi; Michelsen, Anders; Jonasson, Sven Evert

    2005-01-01

    Soil microarthropod responses to long-term soil warming and increased fertilisation by addition of NKP or litter were assessed in three subarctic ecosystems. The experiment was carried out at three different field sites, where temperature and fertilisation manipulations had been running for 3......-5 years (glade), 11 years (fellfield), and 12 years (heath) at the time of sampling. In the glade soil, warming led to decreases in Collembola and Gamasida, and increases in Oribatida, although effects were inconsistent between years. Actinedida densities were increased by fertilization, while Acaridida...... had higher densities in the treatment with both fertilisation and warming. In the fellfield, we found increased densities of Oribatida, Gamasida and Actinedida in the fertilised treatments, and some increases in Oribatida and decreases in Collembola and Gamasida in warming treatments. In the heath...

  9. Effects of long-term fertilization on grain and soil in yellow contents of Zn, B, Cu, Fe and Mn in rice paddy fields of southern China%长期不同施肥对南方黄泥田水稻子粒与土壤锌、硼、铜、铁、锰含量的影响

    Institute of Scientific and Technical Information of China (English)

    王飞; 林诚; 李清华; 何春梅; 李昱; 邱珊莲; 林新坚

    2012-01-01

    在福建黄泥田长期定位施肥试验的第26年,研究了不同施肥模式对水稻子粒与土壤微量元素含量的影响。结果表明,与不施肥(CK)相比,化肥+牛粪(NPKM)、化肥+秸秆还田(NPKS)及单施化肥(NPK)处理的水稻子粒Zn、B、Cu含量均有不同程度的提高,并尤以NPKM处理最为明显,三种微量元素含量分别提高14.3%、25.1%、465.2%,均达差异显著水平。NPKM与NPKS处理还不同程度地提高了子粒Mn含量,但各施肥处理的子粒Fe含量均显著降低。各施肥处理尤其是NPKM与NPKS均显著提高了子粒微量元素吸收量。NPK处理的土壤有效B、Fe、Zn、Cu含量与CK相比均呈下降趋势,且有效Zn、Mn含量较试验前土壤分别降低了36.4%与24.6%,而NPKM与NPKS处理缓解了下降趋势,且NPKM处理的土壤有效Zn、B、Mn含量分别较CK提高46.6%、52.0%、43.0%,均达差异显著水平。土壤有机质与子粒B、Cu、Zn含量呈显著正相关,子粒必需氨基酸、粗蛋白与子粒Zn含量呈显著正相关。以上结果说明,长期化肥配施牛粪或秸秆还田有利于提高水稻子粒Zn、B、Cu等微量元素含量和产量,改善子粒营养品质,一定程度上又可缓解土壤有效微量元素含量的下降,是适合南方黄泥田的施肥模式。%Based on data collected at the 26th year of a long term fertilization experiment in the yellow paddy in Fujian, we investigated the influences of different long-term fertilization regimes on the contents of micronutrients in rice grain and soil. The results show that compared with the control (without fertilization, CK), the contents of Zn, B and Cu of rice grains under the treatments of chemical fertilizer plus cattle manure ( NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK) are all increased more or less, especially under the treatment of NPKM which are

  10. Impact of Long-Term Fertilization on Community Structure of Ammonia Oxidizing and Denitrifying Bacteria Based on amoA and nirK Genes in a Rice Paddy from Tai Lake Region, China

    Institute of Scientific and Technical Information of China (English)

    JIN Zhen-jiang; LI Lian-qing; LIU Xiao-yu; PAN Gen-xing; Qaiser Hussein; LIU Yong-zhuo

    2014-01-01

    Ammonia oxidizing (AOB) and denitrifying bacteria (DNB) play an important role in soil nitrogen transformation in natural and agricultural ecosystems. Effects of long-term fertilization on abundance and community composition of AOB and DNB were studied with targeting ammonia monooxygenase (amoA) and nitrite reductase (nirK) genes using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR, respectively. A ifeld trial with different fertilization treatments in a rice paddy from Tai Lake region, centre East China was used in this study, including no fertilizer application (NF), balanced chemical fertilizers (CF), combined organic/inorganic fertilizer of balanced chemical fertilizers plus pig manure (CFM), and plus rice straw return (CFS). The abundances and richnesses of amoA and nirK were increased in CF, CFM and CFS compared to NF. Principle component analysis of DGGE proifles showed signiifcant difference in nirK and amoA genes composition between organic amended (CFS and CFM) and the non-organic amended (CF and NF) plots. Number of amoA copies was signiifcantly positively correlated with normalized soil nutrient richness (NSNR) of soil organic carbon (SOC) and total nitrogen (T-N), and that of nirK copies was with NSNR of SOC, T-N plus total phosphorus. Moreover, nitriifcation potential showed a positive correlation with SOC content, while a signiifcantly lower denitriifcation potential was found under CFM compared to under CFS. Therefore, SOC accumulation accompanied with soil nutrient richness under long-term balanced and organic/inorganic combined fertilization promoted abundance and diversity of AOB and DNB in the rice paddy.

  11. Captopril-induced reduction of regurgitation fraction in aortic insufficiency: Acute and long-term effects

    Energy Technology Data Exchange (ETDEWEB)

    Kropp, J.; Heck, I.; Reske, S.N.; Biersack, H.J.; Mattern, H.; Winkler, C.; Polikl, M.

    1985-05-01

    In aortic insufficiency (AI) the inhibition of the stimulated Renin-Angiotensin-System (RAS) by Captopril (C) reduced afterload and leads consequently to a diminished regurgitation fraction (RF). In 17 patients (pts) with pure severe AI RF, left ventricular ejection fraction (LVEFE) and heart rate were determined before (1) and 1 hr after (2) administration of 25 mg of C.Long term dosis was 3 x 25 mg of C and follow up time was 3-11 months (medium:6). The values were determined by gated radionuclide ventriculography using red blood cells labeled in vivo with 15 mCi Tc-99mROI's were selected over both ventricles in enddiastolic and endsystolic frames. Ventricular boundaries were defined by a fourier phase image overlay. RF was calculated by the background corrected count rate ratio of left and right ventricular ROI. Systolic and diastolic blood pressure (BPs,BPd), plasma levels of angiotensin I,II(A1,A2) and the activity of angiotensin converting enzyme (ACE) were determined before and 1 hr after C administration. After C there is a decrease in RF which persists in the long term follow period in up to to now 8 pts. The authors conclude: inhibition of ACE reduces significantly aortic regurgitation in patients with AI and has thus a beneficial effect on left ventricular performance. This effect persists in long term treatment and therefore seems beneficial to delay the point of operation.

  12. Mutual long-term effects of school bullying, victimization, and justice sensitivity in adolescents.

    Science.gov (United States)

    Bondü, Rebecca; Rothmund, Tobias; Gollwitzer, Mario

    2016-04-01

    In the present study, we investigate long-term relations between experiences of aggression at school and the development of justice sensitivity as a personality disposition in adolescents. We assessed justice sensitivity (from the victim, observer, and perpetrator perspective), bullying, and victimization among 565 German 12- to 18-year-olds in a one-year longitudinal study with two measurement points. Latent path analyses revealed gender differences in long-term effects of bullying and victimization on observer sensitivity and victim sensitivity. Experiences of victimization at T1 predicted an increase in victim sensitivity among girls and a decrease in victim sensitivity among boys. Bullying behavior at T1 predicted an increase in victim sensitivity among boys and a decrease in observer sensitivity among girls. We did not find long-term effects of justice sensitivity on bullying and victimization. Our findings indicate that experiences of bullying and victimization have gender-specific influences on the development of moral personality dispositions in adolescents.

  13. Long Term Sugarcane Crop Residue Retention Offers Limited Potential to Reduce Nitrogen Fertilizer Rates in Australian Wet Tropical Environments.

    Science.gov (United States)

    Meier, Elizabeth A; Thorburn, Peter J

    2016-01-01

    The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG) emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1) reduce emissions [e.g., those that reduce nitrous oxide (N2O) emissions by avoiding excess nitrogen (N) fertilizer application], and (2) increase soil organic carbon (SOC) stocks (e.g., by retaining instead of burning crop residues). Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues ('trash'). Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a 'trash blanket' in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location × soil × fertilizer × trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 years after trash blanketing commenced. After this period, there was potential to reduce N fertilizer

  14. [Effects of long-term tillage and rice straw returning on soil nutrient pools and Cd concentration].

    Science.gov (United States)

    Tang, Wen-guang; Xiao, Xiao-ping; Tang, Hai-ming; Zhang, Hai-lin; Chen, Fu; Chen, Zhong-du; Xue, Jian-fu; Yang, Guang-li

    2015-01-01

    The objective of this study was to assess the effects of tillage and straw returning on soil nutrient and its pools, and soil Cd concentration, and to identify the strategies for rational tillage and remediation of Cd contaminated paddy fields. The experiment was established with no-tillage with straw retention (NTS) , rotary tillage with straw incorporation (RTS) , conventional plow tillage with straw incorporation (CTS), conventional plow tillage with straw removed ( CT) from 2005 to 2013. The results indicated that tillage and rice straw retention had a great impact on soil properties at 0-10 cm soil depth. The soil aeration, and concentrations of soil nutrient and soil Cd increased under CTS, CT, and RTS. Due to the shallow plow layers, soil nutrient pools and the Cd concentration in rice shoot decreased in long-term tilled soil. Under long-term no-tillage, the soil bulk, soil nutrient pools and Cd concentration in rice shoot increased, but concentrations of soil nutrients decreased. In addition, rice straw returning significantly increased the soil nutrient concentrations, cation exchange capacity, depth of plow layer, and soil nutrient pools. However, the Cd in the rice straw was also returned to the soil by rice straw returning, which would not benefit the remediation of soil Cd. Therefore, it is necessary to improve tillage and straw retention practices due to the disadvantages of long-term continuous single tillage method and rice straw returning practices. Some recommended managements (e.g., rotational tillage or subsoiling, reducing straw returning amount, and rotational straw returning) could be good options in enhancing soil fertility and remedying soil pollution.

  15. The effects of long-term management on patterns of carbon storage in a northern highbush blueberry production system.

    Science.gov (United States)

    Nemeth, Denise; Lambrinos, John G; Strik, Bernadine C

    2017-02-01

    Perennial crops potentially provide a sink for atmospheric carbon. However, there is a poor understanding of how perennial crops differ in their carbon allocation patterns, and few studies have tested how agronomic practices such as fertilization influence long-term patterns of carbon allocation in actual production systems. In this study, we report results of a long-term field experiment that tested the individual and combined effects of organic matter incorporation and nitrogen fertilization on carbon allocation. The mature (nine-year-old) blueberry plants in this study had an average standing carbon stock of 1147gCm(-2) and average annual Net Primary Production (NPP) of 523gCm(-2)yr(-1), values that are similar to those reported for other woody crops. Forty-four percent of blueberry annual NPP was sequestered in persistent biomass, 19% was exported as harvested fruit, and 37% entered the detrital pathway. Nitrogen applied at rates typical for blueberry production throughout the span of the study had no significant effect on total plant or soil C. However, pre-planting organic matter incorporation and periodic mulching with sawdust significantly increased both soil organic matter and soil C. Pre-planting organic matter incorporation also increased total standing plant C nine years later at maturity. At the field scale, we estimate that fields receiving pre-planting organic matter incorporation would have 4.8% (4.5Mgha(-1)) more standing C relative to non-amended fields, although the difference is within the range of uncertainty of the estimated values. These results suggest that blueberry production can provide a valuable medium-term carbon store that is comparable in magnitude to that of temperate tree crops, but overall carbon budgets are influenced by management practices over the first decade after planting.

  16. Evaluation of the leucine incorporation technique for detection of pollution-induced community tolerance to copper in a long-term agricultural field trial with urban waste fertilizers

    DEFF Research Database (Denmark)

    Lekfeldt, Jonas Duus Stevens; Magid, Jakob; Holm, Peter Engelund

    2014-01-01

    Copper (Cu) is known to accumulate in agricultural soils receiving urban waste products as fertilizers. We here report the use of the leucine incorporation technique to determine pollution-induced community tolerance (Leu-PICT) to Cu in a long-term agricultural field trial. A significantly...... speciation and bioavailability artifacts during Leu-PICT detection. Hence, the agricultural application of urban wastes (sewage sludge or composted municipal waste) simulating more than 100 years of use did not result in sufficient accumulation of Cu to select for Cu resistance. Our findings also have...

  17. Long-term effects of interference on short-term memory performance in the rat

    Science.gov (United States)

    Missaire, Mégane; Fraize, Nicolas; Joseph, Mickaël Antoine; Hamieh, Al Mahdy; Parmentier, Régis; Marighetto, Aline; Salin, Paul Antoine; Malleret, Gaël

    2017-01-01

    A distinction has always been made between long-term and short-term memory (also now called working memory, WM). The obvious difference between these two kinds of memory concerns the duration of information storage: information is supposedly transiently stored in WM while it is considered durably consolidated into long-term memory. It is well acknowledged that the content of WM is erased and reset after a short time, to prevent irrelevant information from proactively interfering with newly stored information. In the present study, we used typical WM radial maze tasks to question the brief lifespan of spatial WM content in rodents. Groups of rats were submitted to one of two different WM tasks in a radial maze: a WM task involving the repetitive presentation of a same pair of arms expected to induce a high level of proactive interference (PI) (HIWM task), or a task using a different pair in each trial expected to induce a low level of PI (LIWM task). Performance was effectively lower in the HIWM group than in LIWM in the final trial of each training session, indicative of a “within-session/short-term” PI effect. However, we also observed a different “between-session/long-term” PI effect between the two groups: while performance of LIWM trained rats remained stable over days, the performance of HIWM rats dropped after 10 days of training, and this impairment was visible from the very first trial of the day, hence not attributable to within-session PI. We also showed that a 24 hour-gap across training sessions known to allow consolidation processes to unfold, was a necessary and sufficient condition for the long-term PI effect to occur. These findings suggest that in the HIWM task, WM content was not entirely reset between training sessions and that, in specific conditions, WM content can outlast its purpose by being stored more permanently, generating a long-term deleterious effect of PI. The alternative explanation is that WM content could be transferred and

  18. Testicular germ cell tumor: Short and long-term side effects of treatment among survivors.

    Science.gov (United States)

    Gil, Thierry; Sideris, Spyridon; Aoun, Fouad; van Velthoven, Roland; Sirtaine, Nicolas; Paesmans, Marianne; Ameye, Lieveke; Awada, Ahmad; Devriendt, Daniel; Peltier, Alexandre

    2016-09-01

    Long-term prognosis of germ cell tumor (GCT) types is excellent, however, treatment is associated with non-negligible complication rates and a negative impact on quality of life. The present study described treatment results in terms of survival, both short and long-term toxicity, and paternity rates in a cohort of patients treated at Jules Bordet Institute, University ULB of Brussels (Brussels, Belgium). The present study analyzed the data of a cohort of patients with GCT types. Pre-operative patient and tumor characteristics were described. Performance status, pulmonary function tests and renal clearance prior to chemotherapy were noted. Chemotherapeutic regimens and their associated toxicities were analyzed. The duration to event-free, cancer-specific and overall survivals were estimated using Kaplan-Meier curves. A total of 115 patients (median age, 31-years-old) were treated for a GCT at Jules Bordet Institute. At a median follow-up of 6-years, 11 (10%) patients had relapsed and 2 (2%) developed a second malignant neoplasm. At the final follow-up, 97 (89%) and 6 (5.5%) patients exhibited complete and partial remission, respectively. A total of 6% of patients exhibited a progressive disease. In terms of short-term toxicity, 11% of patients presented with febrile neutropenia. The 10-year overall survival rate and relapse-free survival rate were 93.4 and 89.8%, respectively. The paternity rate post-treatment was 27%. Testicular GCT survivors suffered from short- and long-term treatment-associated side effects on both a physical and psychological level. A long-term close follow-up is necessary in order to assist the patient with these treatment-induced complications.

  19. Long-Term Effects of Antiviral Therapy in Patients with Chronic Hepatitis C

    Directory of Open Access Journals (Sweden)

    Tatehiro Kagawa

    2010-01-01

    Full Text Available Chronic hepatitis C is a major cause of chronic liver disease globally, and the natural history of progression may lead to cirrhosis with liver failure, hepatocellular carcinoma, and premature liver-related death. Emerging data demonstrates that interferon-based therapy, particularly among those achieving a sustained virologic response (SVR, is associated with long-term persistence of SVR, improved fibrosis and inflammation scores, reduced incidence of hepatocellular carcinoma, and prolonged life expectancy. This reduction in the rate of progression has also been demonstrated in patients with chronic hepatitis C and cirrhosis in some but not all studies. The majority of these results are reported with standard interferon therapy, and long-term results of peginterferon plus ribavirin therapy with a higher likelihood of SVR should have a yet greater impact on the population of treated patients. The impact on slowing progression is greatest in patients with an SVR, less in relapsers, and equivocal in nonresponders. Thus, the natural history of chronic hepatitis C after completion of antiviral therapy is favorable with achievement of an SVR, although further data are needed to determine the likely incremental impact of peginterferon plus ribavirin, late long-term effects of therapy, and the benefit of treatment in patients with advanced hepatic fibrosis.

  20. Effects of long-term iloprost treatment on right ventricular function in patients with Eisenmenger syndrome.

    Science.gov (United States)

    Chon, Min Ku; Cho, Kyoung Im; Cha, Kwang Soo; Seo, Jeong Sook; Kim, Dong Soo

    2017-05-01

    Right ventricular (RV) function is an important prognostic factor of pulmonary arterial hypertension (PAH), but there is insufficient data regarding RV function after long-term inhaled iloprost treatment. We evaluated the effect of long-term iloprost treatment on RV function in patients with Eisenmenger syndrome (ES). Eleven consecutive patients with ES associated with congenital heart disease underwent echocardiographic measurements at baseline and 48 weeks after iloprost therapy. In addition, we recorded World Health Organization (WHO) functional class, 6-minute walk distance (6MWD), systemic arterial oxygen saturation (SaO2), and laboratory values such as hemoglobin, serum creatinine, and N-terminal pro-B natriuretic peptide. After 48 weeks of iloprost therapy, mean pulmonary arterial pressure (mPAP), pulmonary arterial systolic pressure (PASP), and pulmonary vascular resistance (PVR) were significantly decreased [mPAP, 42.5 (38.5-61.0) to 36.5 (29.1-40.0)mmHg; PASP, 92.6±19.9 to 74.5±23.8mmHg; PVR, 23.4 (19.8-26.0) to 23.4 (19.8-26.0)Wood unit respectively, all piloprost therapy may provide insight on the efficacy of long-term iloprost treatment for RV functional improvement, which is a prognostic factor in patients with ES. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  1. Evidence of long term global decline in the Earth's thermospheric densities apparently related to anthropogenic effects

    Science.gov (United States)

    Keating, G. M.; Tolson, R. H.; Bradford, M. S.

    2000-05-01

    A study was performed of the long-term orbital decay of five Earth satellites with perigee altitudes averaging near 350km. To decouple long-term trend measurements from the effects of solar variability, measurements were evaluated during the years of solar minimum (1976, 1986 and 1996). Atmospheric densities derived from these essentially global measurements showed substantial evidence of a decline averaging 9.8 ± 2.5% in thermospheric density over 20 years pointing toward a long-term cooling of the upper atmosphere. Increases in greenhouse gases induced by human activity are hypothesized to warm the Earth's surface and lower atmosphere, but strongly cool the upper atmosphere. Assuming that the 10% increase in CO2 over these 20 years caused cooling resulting in the 10% decline in density, a doubling of CO2 could cause the thermospheric densities measured near 350km to decrease by a factor of 3. This decrease may shrink the altitude of a constant density surface by 40km before the end of the 21st century.

  2. Long-term RF burn-in effects on dielectric charging of MEMS capacitive switches

    KAUST Repository

    Molinero, David G.

    2013-03-01

    This paper experimentally quantified the long-term effects of RF burn-in, in terms of burn-in and recovery times, and found the effects to be semipermanent. Specifically, most of the benefit could be realized after approximately 20 min of RF burn-in, which would then last for several months. Additionally, since similar effects were observed on both real and faux switches, the effects appeared to be of electrical rather than mechanical nature. These encouraging results should facilitate the application of the switches in RF systems, where high RF power could be periodically applied to rejuvenate the switches. © 2001-2011 IEEE.

  3. Long-term Effects of Shrub Encroachment and Grazing on Soil Microbial Composition and Function

    Science.gov (United States)

    Gallery, R. E.; O'Shea, C.; Kwiecien, A.; Predick, K.; Archer, S. R.

    2014-12-01

    Drylands account for ca. 35% of terrestrial net primary productivity and thus play a significant role in global water and biogeochemical cycles. Replacement of grasses by shrubs has been widespread in these systems and has altered rates of erosion and native plant biodiversity and productivity. The net effect of these changes on biogeochemical cycling is not well understood. Projected warmer and drier conditions may further alter the function and stability of these ecosystems and soil resources through direct effects on soil microbiota and plant-microbe interactions. We quantified microbial community responses to long-term livestock grazing and shrub encroachment in a Sonoran Desert grassland. We sought to characterize tipping points where biotic controls over ecosystem processes shift from being 'grass-driven' to 'shrub-driven.' We asked: How do livestock grazing (the predominant land use in dryland ecosystems) and shrub invasion (a predominant land cover change) interact to influence microbial biomass and the relative abundance of bacteria, archaea, and fungi and their extracellular enzyme activities? Surface soil from bare-ground patches, native and invasive grass rhizospheres, and bole and canopy dripline locations in patches of mature mesquite trees in long-term grazed and long-term (70+ y) protected pastures were collected and analyzed for microbial community composition, biomass, potential exoenzyme activities, and a suite of biogeochemical characteristics. We found no differences in microbial communities or the soils associated with native vs. exotic grasses. Overall, mesquite bole patches differed from other patches in all soil characteristics except potential enzyme activity: soil temperature was significantly lower, and total carbon (C) and soil moisture were significantly higher. Potential activities were lowest for bare ground and highest at shrub dripline patches for all seven exoenzymes tested. Mean potential activities for C and phosphorous (P

  4. Dynamic Relationship Between Biologically Active Soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized Soils

    Institute of Scientific and Technical Information of China (English)

    LI Cheng-Liang; XU Jiang-Bing; HE Yuan-Qiu; LIU Yan-Li; FAN Jian-Bo

    2012-01-01

    Biologically active soil organic carbon (BASOC) is an important fraction of soil organic carbon (SOC),but our understanding of the correlation between BASOC and soil aggregate stability is limited.At an ecological experimental station (28° 04′-28° 37′ N,116°41′-117° 09′ E) in Yujiang County,Jiangxi Province,China,we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil (Udic Ferrosols) fertilized with a nitrogen-phosphorus-potassium chemical fertilizer (NPK)without manure or with NPK plus livestock manure or green manure.The dynamics of BASOC was evaluated using CO2 efflux,and soil aggregates were separated according to size using a wet-sieving technique.The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone The BASOC contents in all fertilized soils decreased over time The contents of large aggregates (800-2000μm) dramatically decreased over the first 7 d of incubation,but the contents of small aggregates (< 800.μm) either remained the same or increased,depending on the incubation time and specific aggregate sizes.The aggregate stability did not differ significantly at the beginning and end of incubation,but the lowest stability inall fertilized soils occurred in the middle of the incubation,which implied that the soils had a strong resilience for aggregate stability.The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

  5. Long-Term Effects of Inorganic and Organic Amendments on Organic Carbon in a Paddy Soil of the Taihu Lake Region, China

    Institute of Scientific and Technical Information of China (English)

    MA Li; YANG Lin-Zhang; XIA Li-Zhong; SHEN Ming-Xing; YIN Shi-Xue; LI Yun-Dong

    2011-01-01

    A long-term experiment set up in 1980 compared the effects of applying manures and chemical fertilizers on a paddy soil in the Taihu Lake region, China. Of the fourteen randomly distributed treatments consisting of different combinations of organic manure, inorganic nitrogen (N), phosphorus (P), and potassium (K), and rice straw, eight were selected for the present study in 2007. Application of organic manure plus straw significantly increased soil organic carbon (SOC) content of the topsoil (0-10 cm) compared to that of chemical fertilizers alone. The content of SOC was relatively stable in the 10-30 cm layer in the chemical fertilizer treatments and in the 20-40 cm layer in the manure treatments. The stable carbon isotope ratio (δ13C) ranged from -24‰ to -28‰ and increased gradually with depth. The content of SOC was significantly (P < 0.05) negatively correlated with δ13C. In the 0-20 cm layer, the δ13C value significantly decreased in the treatments of manure alone (M), manure and chemical N and P fertilizers (MNP), manure and chemical N, P, and K fertilizers (MNPK), manure, rice straw, and chemical N fertilizer (MRN), and chemical N fertilizer and rice straw (CNR), as compared with the no-fertilizer control. In the 30-50 cm layer, however, the ratio significantly increased in all the treatments except Treatment CNR. Mineralization of organic C peaked in the first 2-4 d of incubation and gradually leveled off thereafter over the first 3 weeks, being faster in the manure treatments than the chemical fertilizer treatments. The average rate of mineralization varied from 55.36 to 75.46 mL CO2 kg-1 d-1 and that of stable mineralization from 10 to 20 mL CO2 kg-1 d-1. In eight weeks of incubation, cumulative mineralization was always higher in the manure treatments than the chemical fertilizer treatments, being the highest in Treatment MRN. Combined humus in the soil was mainly (over 50%) composed of tightly combined fraction. The loosely combined humus and

  6. The Long Term Effect on Children of Increasing the Length of Parents' Birth Related Leave

    DEFF Research Database (Denmark)

    Wurtz, Astrid

        The length of parents' total birth related leave was increased with almost 50% in 1984 in Denmark. The previous length of the Danish maternity leave was long, especially compared to e.g. the U.S. today. This paper investigates the long term effects on children of increasing length of birth...... related leave from 14 to 20 weeks. We use differences-in-differences regression discontinuity design to identify the causal effect of the leave reform and it estimated whether such a large increase in the mandated leave period has a large measurable and persistent effect on children's cognitive...... birth related leave period from 14 to 20 weeks.  ...

  7. Long term adverse effects related to nucleoside reverse transcriptase inhibitors: clinical impact of mitochondrial toxicity.

    Science.gov (United States)

    Maagaard, Anne; Kvale, Dag

    2009-01-01

    Antiretroviral treatment (ART) has provided excellent clinical efficacy in HIV infection, and individuals treated for HIV might therefore expect normal duration of life. However, this enthusiasm might be moderated by some devastating long-term adverse effects that are frequently observed in HIV-infected individuals, phenomena that may be even more pronounced as the HIV-infected populations become older and therefore perhaps more susceptible to some of these adverse effects. We here review the clinical impact of mitochondrial toxicity giving rise to many of the adverse effects caused by ART.

  8. Evaluation of the leucine incorporation technique for detection of pollution-induced community tolerance to copper in a long-term agricultural field trial with urban waste fertilizers.

    Science.gov (United States)

    Lekfeldt, Jonas Duus Stevens; Magid, Jakob; Holm, Peter E; Nybroe, Ole; Brandt, Kristian Koefoed

    2014-11-01

    Copper (Cu) is known to accumulate in agricultural soils receiving urban waste products as fertilizers. We here report the use of the leucine incorporation technique to determine pollution-induced community tolerance (Leu-PICT) to Cu in a long-term agricultural field trial. A significantly increased bacterial community tolerance to Cu was observed for soils amended with organic waste fertilizers and was positively correlated with total soil Cu. However, metal speciation and whole-cell bacterial biosensor analysis demonstrated that the observed PICT responses could be explained entirely by Cu speciation and bioavailability artifacts during Leu-PICT detection. Hence, the agricultural application of urban wastes (sewage sludge or composted municipal waste) simulating more than 100 years of use did not result in sufficient accumulation of Cu to select for Cu resistance. Our findings also have implications for previously published PICT field studies and demonstrate that stringent PICT detection criteria are needed for field identification of specific toxicants.

  9. The effectiveness of the JOBS program among the long-term unemployed: A randomized experiment in the Netherlands

    NARCIS (Netherlands)

    Brenninkmeijer, V.; Blonk, R.W.B.

    2012-01-01

    Given the adverse effects of long-term unemployment, it is of major concern that evidence-based interventions are available for the long-term unemployed. Therefore, we examined the effectiveness of the JOBS program, a group training for the unemployed [Caplan, R. D., Vinokur, A. D., Price, R. H. and

  10. Long-term benefit and cost-effectiveness analysis of screening for abdominal aortic aneurysms from a randomized controlled trial

    DEFF Research Database (Denmark)

    Lindholt, Jes S.; Sørensen, J; Søgaard, R

    2010-01-01

    The aim was to estimate long-term mortality benefits and cost-effectiveness of screening for abdominal aortic aneurysm (AAA) in men aged 64-73 years.......The aim was to estimate long-term mortality benefits and cost-effectiveness of screening for abdominal aortic aneurysm (AAA) in men aged 64-73 years....

  11. Mutualistic functioning of indigenous arbuscular mycorrhizae in spring barley and winter wheat after cessation of long-term phosphate fertilization

    NARCIS (Netherlands)

    Dekkers, T.B.M.; Werff, van der P.A.

    2001-01-01

    The influence of 23 years of phosphorus (P) application at three annual rates of 0, 17.5 and 52.5 kg ha-1 on arbuscular mycorrhizal (AM) fungal colonization was studied 10 years after the fertilization treatment ended. The annual application of 52.5 kg ha-1 was about twice the annual crop P

  12. Long-Term Dynamics of Standing Crop and Species Composition after the Cessation of Fertilizer Application to Mown Grassland

    NARCIS (Netherlands)

    Olff, H.; Bakker, J.P.

    1991-01-01

    (1) Current agricultural overproduction in Western Europe has led to an increase in the area of unfertilized grassland. This paper reports an experiment where fertilizer application was stopped to try to restore former species-rich vegetation. (2) Standing crop and species composition of three diffe

  13. The long-term outcome of 946 consecutive couples visiting a fertility clinic in 2001-2003

    NARCIS (Netherlands)

    Donckers, Janneke; Evers, Johannes L. H.; Land, Jolande A.

    Objective: To describe the outcome of fertility work-up, treatment, and dropout in a cohort of subfertile couples in a well-defined area in Western Europe. Design: Prospective cohort study. Setting: Maastricht University Medical Center. Patient(s): Subfertile couples referred by their general

  14. 长期定位施肥对土壤铜、锌形态转化及其空间分布的影响%Effects of Long-term Located Fertilization on the Forms Transformation and Spatial Distribution of Cu and Zn in Soil

    Institute of Scientific and Technical Information of China (English)

    韩晓日; 袁程; 王月; 杨劲峰; 李娜; 张欣昕

    2011-01-01

    The BCR continuous extraction was used to research the soil Cu and Zn contents change and its spatial variability after 31-year fertilization treatments on Shenyang Agricultural University brown earth long-term localization experimental field.The experimental results showed that compared with the baseline,the contents of the water soluble Cu,the weak acid soluble Cu and residual Cu decreased,the contents of oxidizable Cu and reducible Cu decreased in fertilizer area while in organic fertilizer area the trend was opposite;except residual Zn,the contents of other forms increased.The distributions of Cu forms were different in different treatments in topsoil(0-20 cm),residual Zn was the main forms.As for the spatial distribution,with the deepen of soil,the contents of the weak acid soluble,oxidizable and reducible Cu,Zn reduced.Reducible Cu gave the greatest contribution to available Cu and oxidizable Zn gave the greatest contribution to available Zn.%采用改进的BCR连续提取法,对沈阳农业大学棕壤肥料长期定位试验地31年不同施肥处理土壤铜和锌含量变化及其空间变异规律进行研究。结果表明:与试验前相比,耕层(0-20cm)土壤各处理水溶态铜、弱酸溶态铜和残渣态铜含量都有不同程度的减少,可还原态铜和可氧化态铜含量在化肥区有所降低,在有机肥区有所增加;残渣态锌含量明显减少,其他形态锌含量有不同程度的增加。耕层各形态铜分布趋势因处理不同而不同,锌以残渣态为主。在空间分布上,2种元素弱酸溶态、可还原态和可氧化态含量都是随土层的加深而减少。可氧化态铜与有效态铜关系最密切;可还原态锌对有效态锌的贡献最大。

  15. [N2O and CH4 emission from Japan rice fields under different long-term fertilization patterns and its environmental impact].

    Science.gov (United States)

    Luo, Liang-guo; Kondo, Motohiko; Itoh, Sumio

    2010-12-01

    This study intended to investigate the greenhouse gases emission from Japan single cropping paddy fields after 75-year continuous application of ammonium sulfate, composted rice straw with soybean cake, and fresh clover, as well as the environmental impact of the emission. During this long period, field management remained constant in terms of rice cultivation density, irrigation, and equivalent net N fertilization. No significant differences were observed in N2O emission among the fertilization treatments, but the CH4 emission differed significantly between organic amendment and ammonium sulfate application, indicating that long-term organic fertilization didn' t increase N2O emission but promoted CH4 emission. The cumulative global warming potential (GWP) of the CH4 and NO2O from the paddy ecosystem was the greatest (310.7 g CO2e x m(-2)) under fresh clover application, followed by composted rice straw plus soybean cake addition (151 g CO2e x m(-2)), and the least (60.6 g CO2e x m(-2)) under ammonium sulfate application. This study showed that for paddy system, it was CH4 instead of N2O the major factor affecting global warming, and thereby, to control and reduce the CH4 emission from paddy system would be the core in mitigating greenhouse gases emission from paddy field. Long-term consecutive application of composted rice straw plus soybean cake could increase soil organic matter, improve soil fertility, promote rice high-yielding, and as well, mitigate CH4 emission, being the recommendable paddy rice production mode in practice.

  16. Long-term safety and effectiveness of pramipexole in tetrahydrobiopterin deficiency.

    Science.gov (United States)

    Porta, Francesco; Ponzone, Alberto; Spada, Marco

    2016-11-01

    Tetrahydrobiopterin (BH4) deficiencies are inherited neuro-metabolic disorders leading to monoamine neurotransmitters deficiency. An individualized replacement therapy with neurotransmitters precursors is necessary to restore dopaminergic and serotoninergic homeostasis. The correction of dopaminergic tone is complicated, like in Parkinson disease, by l-dopa short half-life and adverse effects. To improve this picture, since 2009 we introduced the non-ergot dopamine agonist pramipexole as an adjunct to l-dopa therapy in the treatment of the most common causes of BH4 deficiency, 6-pyruvoyl tetrahydropterin synthase (PTPS) deficiency and dihydropteridine reductase (DHPR) deficiency. In the short-term period, this approach allowed substantial clinical advantages in affected patients, with amelioration and stabilization of the clinical picture on twice daily treatment administration and no adverse effect. Here we describe the long-term clinical follow-up (83 ± 24 months) of seven patients with BH4 deficiency treated with pramipexole. After a period of good clinical compensation (34 ± 1 months), different impulse control disorders (gambling, compulsive buying, and hypersexuality) were observed in three patients treated with high-dose pramipexole (0.030-0.033 mg/kg/day) beyond adolescence. These psychiatric adverse effects promptly disappeared after curtailing pramipexole dose by 50-60%. Low-dose pramipexole therapy has been safe and effective in the long-term period in all treated patients (59 ± 9 months). High-dose pramipexole therapy in BH4 deficiency can be complicated, like in Parkinson disease, by psychiatric adverse effects. Low-dose pramipexole therapy (∼0.010 mg/kg/day) has been safe and clinically effective on long-term follow-up, representing a helpful therapeutic option in patients with BH4 deficiency.

  17. Hippocampal long term memory: effect of the cholinergic system on local protein synthesis.

    Science.gov (United States)

    Lana, Daniele; Cerbai, Francesca; Di Russo, Jacopo; Boscaro, Francesca; Giannetti, Ambra; Petkova-Kirova, Polina; Pugliese, Anna Maria; Giovannini, Maria Grazia

    2013-11-01

    The present study was aimed at establishing a link between the cholinergic system and the pathway of mTOR and its downstream effector p70S6K, likely actors in long term memory encoding. We performed in vivo behavioral experiments using the step down inhibitory avoidance test (IA) in adult Wistar rats to evaluate memory formation under different conditions, and immunohistochemistry on hippocampal slices to evaluate the level and the time-course of mTOR and p70S6K activation. We also examined the effect of RAPA, inhibitor of mTORC1 formation, and of the acetylcholine (ACh) muscarinic receptor antagonist scopolamine (SCOP) or ACh nicotinic receptor antagonist mecamylamine (MECA) on short and long term memory formation and on the functionality of the mTOR pathway. Acquisition test was performed 30 min after i.c.v. injection of RAPA, a time sufficient for the drug to diffuse to CA1 pyramidal neurons, as demonstrated by MALDI-TOF-TOF imaging. Recall test was performed 1 h, 4 h or 24 h after acquisition. To confirm our results we performed in vitro experiments on live hippocampal slices: we evaluated whether stimulation of the cholinergic system with the cholinergic receptor agonist carbachol (CCh) activated the mTOR pathway and whether the administration of the above-mentioned antagonists together with CCh could revert this activation. We found that (1) mTOR and p70S6K activation in the hippocampus were involved in long term memory formation; (2) RAPA administration caused inhibition of mTOR activation at 1 h and 4 h and of p70S6K activation at 4 h, and long term memory impairment at 24 h after acquisition; (3) scopolamine treatment caused short but not long term memory impairment with an early increase of mTOR/p70S6K activation at 1 h followed by stabilization at longer times; (4) mecamylamine plus scopolamine treatment caused short term memory impairment at 1 h and 4 h and reduced the scopolamine-induced increase of mTOR/p70S6K activation at 1 h and 4 h; (5

  18. The long-term effect of 1550 nm erbium:glass fractional laser in acne vulgaris.

    Science.gov (United States)

    Liu, Yale; Zeng, Weihui; Hu, Die; Jha, Smita; Ge, Qin; Geng, Songmei; Xiao, Shengxiang; Hu, Guanglei; Wang, Xiaoxiao

    2016-04-01

    We evaluated the short-term and long-term effects of the 1550 nm erbium:glass (Er:glass) fractional laser in the treatment of facial acne vulgaris. Forty-five (9 male and 36 female) acne patients were treated 4 times at 4-week intervals with the following parameters: 169 spot density and 15-30 mJ/cm(2) fluence. There was no control group. The laser spots were adjustable (maximum overlap: 20%) according to the treatment area, and delivered in rows in order to cover all the face. Clinical photographs were taken. The IGA scores and lesion counts were performed for each treatment. Their current state was obtained by phone call follow-up to determine the long-term effect and photographs were offered by themselves or taken in hospital. After four treatments, all patients had an obvious reduction of lesion counts and IGA score and the peak lesion counts decreased to 67.7% after the initial four treatment sessions. For long-term effect, 8 patients lost follow-up, hence 37 patients were followed-up. 8 patients were 2-year follow up, 27 at the 1-year follow-up, and all patients at the half-year follow-up. The mean percent reduction was 72% at the half-year follow-up, 79 at the 1-year follow-up and 75% at the 2-year follow-up. Side effects and complications were limited to transient erythema and edema, and few patients suffered from transient acne flare-ups and sensitivity. All patients responded that their skin was less prone to oiliness. In conclusion, acne can be successfully treated by 1550 nm Er:glass fractional laser, with few side effects and prolonged acne clearing.

  19. Long-term functional side-effects of stimulants and sedatives in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Kennedy Matsagas

    Full Text Available BACKGROUND: Small invertebrate animals, such as nematodes and fruit flies, are increasingly being used to test candidate drugs both for specific therapeutic purposes and for long-term health effects. Some of the protocols used in these experiments feature such experimental design features as lifelong virginity and very low densities. By contrast, the ability of both fruit flies and nematodes to resist stress is frequently correlated with their longevity and other functional measures, suggesting that low-stress assays are not necessarily the only useful protocol for testing the long-term effects of drugs. METHODOLOGY/PRINCIPAL FINDINGS: Here we report an alternative protocol for fruit fly drug-testing that maximizes reproductive opportunities and other types of interaction, with moderately high population densities. We validate this protocol using two types of experimental tests: 1. We show that this protocol detects previously well-established genetic differences between outbred fruit fly populations. 2. We show that this protocol is able to distinguish among the long-term effects of similar types of drugs within two broad categories, stimulants and tranquilizers. CONCLUSIONS: Large-scale fly drug testing can be conducted using mixed-sex high-density cage assays. We find that the commonly-used stimulants caffeine and theobromine differ dramatically in their chronic functional effects, theobromine being more benign. Likewise, we find that two generic pharmaceutical tranquilizers, lithium carbonate and valproic acid, differ dramatically in their chronic effects, lithium being more benign. However, these findings do not necessarily apply to human subjects, and we thus do not recommend the use of any one substance over any other.

  20. Effects of treadmill exercise intensity on spatial working memory and long-term memory in rats.

    Science.gov (United States)

    Wang, Xiao-Qin; Wang, Gong-Wu

    2016-03-15

    Moderate exercise promotes learning and memory. Most studies mainly focused on memory exercise effects of in the ageing and patients. There is lack of quantitative research about effect of regular exercise intensity on different memory types in normal subjects. Present study investigated the effects of different intensities of treadmill exercise on working memory and long-term memory. Fifty female Wistar rats were trained by T-maze delayed spatial alternation (DSA) task with 3 delays (10s, 60s and 300s). Then they got a 30min treadmill exercise for 30days in 4 intensities (control, 0m/min; lower, 15m/min; middle, 20m/min, and higher, 30m/min). Then animals were tested in DSA, passive avoidance and Morris water maze tasks. 1. Exercise increased the neuronal density of hippocampal subregions (CA1, CA3 and dentate gyrus) vs. naïve/control. 2. In DSA task, all groups have similar baseline, lower intensity improved 10s delay accuracy vs. baseline/control; middle and higher intensities improved 300s delay accuracy vs. baseline/control. 3. In water maze learning, all groups successfully found the platform, but middle intensity improved platform field crossing times vs. control in test phase. Present results suggested that treadmill exercise can improve long-term spatial memory and working memory; lower intensity benefits to short-term delayed working memory, and middle or higher intensity benefits to long-term delayed working memory. There was an inverted U dose-effect relationship between exercise intensity and memory performance, but exercise -working memory effect was impacted by delay duration. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Effects of long-term compost application on carbon content and soil physical properties

    Science.gov (United States)

    Eden, Marie; Houot, Sabine

    2013-04-01

    Biological treatment through composting of organic wastes fulfils multiple purposes: it not only reduces the amount of waste stored in landfills but can also provide agricultural soils with organic amendments, which affect physicochemical soil properties and reduce the use of mineral fertilizers. However, the impacts of different types of amendments are not yet fully understood, as quantity and quality of the exogenous organic matter (EOM) applied vary greatly and numerous other parameters are affected as well, such as pH, heavy metal content, or nutrient availability. The objective of this project was to investigate the effect of different organic amendments - via simulations - on water holding capacity (WHC) and particularly plant available water (PAW), in regard to irrigation needs. The long-term field experiment "Qualiagro" (INRA - Veolia Environment collaboration) was established in Feucherolles, France in 1998, where five treatments were designed, each with two levels of mineral nitrogen (N) addition: minimal and optimal. Farmyard manure (FYM) and three types of compost - all applied every other year at a rate of 4 t carbon ha-1 - gave rise to varying organic carbon (OC) contents and were compared to a control treatment. The treatments changed the soil's OC content from initially ~10.5 g kg-1 to a range of 9.35 to 15.58 g kg-1. An increased OC content can enhance WHC by increasing total porosity/ reducing bulk density. The PAW - the difference between field capacity (FC) and permanent wilting point (WP); predicted with pedotransfer functions related to OC - increases, if the increase at FC is larger than that at WP. With a higher amount of PAW, the need to irrigate fields - to ensure sufficient water availability for plant growth - decreases. At the same time, soil bulk density (ρd) affects root growth; denser soils can lead to reduced rooting depth. Both of these effects were considered when employing a simple soil water balance model (BUDGET; http

  2. Short- and long-term cognitive effects of chronic cannabinoids administration in late-adolescence rats.

    Directory of Open Access Journals (Sweden)

    Hila Abush

    Full Text Available The use of cannabis can impair cognitive function, especially short-term memory. A controversial question is whether long-term cannabis use during the late-adolescence period can cause irreversible deficits in higher brain function that persist after drug use stops. In order to examine the short- and long-term effects of chronic exposure to cannabinoids, rats were administered chronic i.p. treatment with the CB1/CB2 receptor agonist WIN55,212-2 (WIN; 1.2 mg/kg for two weeks during the late adolescence period (post-natal days 45-60 and tested for behavioral and electrophysiological measures of cognitive performance 24 hrs, 10 and 30 days after the last drug injection. The impairing effects of chronic WIN on short-term memory in the water maze and the object recognition tasks as well as long-term potentiation (LTP in the ventral subiculum (vSub-nucleus accumbens (NAc pathway were temporary as they lasted only 24 h or 10 d after withdrawal. However, chronic WIN significantly impaired hippocampal dependent short-term memory measured in the object location task 24 hrs, 10, 30, and 75 days after the last drug injection. Our findings suggest that some forms of hippocampal-dependent short-term memory are sensitive to chronic cannabinoid administration but other cognitive impairments are temporary and probably result from a residue of cannabinoids in the brain or acute withdrawal effects from cannabinoids. Understanding the effects of cannabinoids on cognitive function may provide us with tools to overcome these impairments and for cannabinoids to be more favorably considered for clinical use.

  3. Long-term spacing effect benefits in developmental amnesia: case experiments in rehabilitation.

    Science.gov (United States)

    Green, Janet L; Weston, Tina; Wiseheart, Melody; Rosenbaum, R Shayna

    2014-09-01

    The spacing effect describes the typical finding that repeated items are remembered best when additional items are introduced between each repetition than when the repetitions occur in immediate succession. In this study, we investigated the nature and limits of the spacing effect in the developmental amnesic case H.C. In Experiment 1, we compared the performance of H.C. to that of controls on a short-term, free recall, verbal learning spacing paradigm while controlling for retention interval (timing of item review and recall). In Experiment 2, we compared the performance of H.C. to that of controls on a multiday, cued recall, verbal learning spacing paradigm, in which memory was assessed after 1 week. In both experiments, H.C. demonstrated a spacing effect comparable to the effect exhibited by controls. In Experiment 1, her final recall memory for long-lag (spaced) items was better than recall for no-lag (massed) items t(23) = 10.99, p memory for next-day-reviewed (spaced) items was better than cued recall for same-day-reviewed (massed) items, t(20) = 17.6, p memory development and is the first to show long-term benefits of spacing in amnesia. Substantially slower learning-to-criterion suggests an alternate mechanism supporting the spacing effect, perhaps independent of the hippocampus. Spacing should be considered as a candidate memory intervention technique given its effectiveness in both short- and long-term learning settings. (c) 2014 APA, all rights reserved.

  4. Long-term effects of growth hormone (GH) replacement in men with childhood-onset GH deficiency

    NARCIS (Netherlands)

    Ter Maaten, JC; De Boer, H; Kamp, O; Stuurman, L; Van der Veen, EA

    1999-01-01

    Short term GH replacement therapy has been shown to improve body composition and exercise capacity. It is not yet known whether GH replacement remains beneficial over the long term. We assessed the effects of long term GH replacement on body composition, bone mineral density, and cardiac function. T

  5. Effect of Clickers "versus" Online Homework on Students' Long-Term Retention of General Chemistry Course Material

    Science.gov (United States)

    Gebru, Misganaw T.; Phelps, Amy J.; Wulfsberg, Gary

    2012-01-01

    This study reports the effects of student response systems (clickers) "versus" online homework on students' long-term retention of General Chemistry I course material. Long-term content retention was measured by a comprehensive yearlong American Chemical Society (ACS) GC97 exam administered seven months after students had completed the General…

  6. Effect of Clickers "versus" Online Homework on Students' Long-Term Retention of General Chemistry Course Material

    Science.gov (United States)

    Gebru, Misganaw T.; Phelps, Amy J.; Wulfsberg, Gary

    2012-01-01

    This study reports the effects of student response systems (clickers) "versus" online homework on students' long-term retention of General Chemistry I course material. Long-term content retention was measured by a comprehensive yearlong American Chemical Society (ACS) GC97 exam administered seven months after students had completed the General…

  7. Potential effect of conservation tillage on sustainable land use : a review of global long-term studies

    NARCIS (Netherlands)

    Wang Xiaobin,; Cai, D.; Hoogmoed, W.B.; Oenema, O.; Perdok, U.D.

    2006-01-01

    Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation tillage research, this paper discusses the long-term effect of conservation tillage on

  8. Long-term Effects on Cognitive Trajectories of Postmenopausal Hormone Therapy in Two Age Groups.

    Science.gov (United States)

    Espeland, Mark A; Rapp, Stephen R; Manson, JoAnn E; Goveas, Joseph S; Shumaker, Sally A; Hayden, Kathleen M; Weitlauf, Julie C; Gaussoin, Sarah A; Baker, Laura D; Padula, Claudia B; Hou, Lifang; Resnick, Susan M

    2017-06-01

    Postmenopausal hormone therapy may have long-term effects on cognitive function depending on women's age. Postintervention follow-up was conducted with annual cognitive assessments of two randomized controlled clinical trial cohorts, beginning an average of 6-7 years after study medications were terminated: 1,376 women who had enrolled in the Women's Health Initiative when aged 50-54 years and 2,880 who had enrolled when aged 65-79 years. Women had been randomly assigned to 0.625mg/d conjugated equine estrogens (CEE) for those with prior hysterectomy (mean 7.1 years), CEE with 2.5mg/d medroxyprogesterone acetate for those without prior hysterectomy (mean 5.4 years), or matching placebos. Hormone therapy, when prescribed to women aged 50-54 years, had no significant long-term posttreatment effects on cognitive function and on changes in cognitive function. When prescribed to older women, it was associated with long-term mean (SE) relative decrements (standard deviation units) in global cognitive function of 0.081 (0.029), working memory of 0.070 (0.025), and executive function of 0.054 (0.023), all p therapy regimen, prior use, or years from last menstrual period. Mean intervention effects were small; however, the largest were comparable in magnitude to those seen during the trial's active intervention phase. CEE-based hormone therapy delivered near the time of menopause provides neither cognitive benefit nor detriment. If administered in older women, it results in small decrements in several cognitive domains that remain for many years.

  9. Short- and Long-Term Effects of Inhaled Iloprost Therapy in Children With Pulmonary Arterial Hypertension

    Science.gov (United States)

    Ivy, D. Dunbar; Doran, Aimee K.; Smith, Kelly J.; Mallory, George B.; Beghetti, Maurice; Barst, Robyn J.; Brady, Daniela; Law, Yuk; Parker, Donna; Claussen, Lori; Abman, Steven H.

    2011-01-01

    Objectives This study investigated the short- and long-term outcome of children with pulmonary arterial hypertension (PAH) treated with inhaled iloprost. Background Inhaled iloprost has been approved for the treatment of adults with PAH, but little is known about the effects in children with PAH. Methods We evaluated the acute effects of inhaled iloprost on hemodynamic status and lung function and the response to long-term therapy in 22 children (range 4.5 to 17.7 years) with PAH (idiopathic, n = 12; congenital heart disease, n = 10). Cardiac catheterization, standard lung function testing before and after iloprost inhalation, 6-min walk test, World Health Organization functional class, and hemodynamic parameters were monitored. Results Acute administration of inhaled iloprost lowered mean pulmonary artery pressure equivalent to the response to inhaled nitric oxide with oxygen. Acute iloprost inhalation reduced forced expiratory volume in 1 s and mid-volume forced expiratory flow by 5% and 10%, respectively, consistent with acute bronchoconstriction. At 6 months, functional class improved in 35%, decreased in 15%, and remained unchanged in 50% of children. Sixty-four percent of patients continued receiving long-term iloprost therapy, 36% stopped iloprost, due to lower airway reactivity, clinical deterioration, or death. In 9 patients on chronic intravenous prostanoids, 8 transitioned from intravenous prostanoids to inhaled iloprost, which continued during follow-up. Conclusions Inhaled iloprost caused sustained functional improvement in some children with PAH, although inhaled iloprost occasionally induced bronchoconstriction. Most patients tolerated the transition from intravenous to inhaled prostanoid therapy. Clinical deterioration, side effects, and poor compliance, owing to the frequency of treatments, could limit chronic treatment in children. PMID:18191742

  10. Effect of Fertilization on Soil Fertility and Wheat Yield of Dryland in the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    HAO Ming-De; FAN Jun; WEI Xiao-Rong; PEN Lin-Fa; LAI Lu

    2005-01-01

    Long-term fertility experiments have become an important tool for investigating the sustainability of cropping systems.Therefore, a long-term (18-year) fertilization experiment was conducted in Changwu County, Shaanxi Province, China,to ascertain the effect of the long-term application of chemical fertilizers and manure on wheat yield and soil fertility in the Loess Plateau, so as to provide a scientific basis for sustainable land management. The experiment consisted of nine fertilizer treatments with three replicates arranged in a completely randomized design: 1) CK (no fertilizer); 2) N (N 120 kg ha-i); 3) P (P 26.2 kg ha-1); 4) NP (N 120, P 26.2 kg ha-1); 5) M (manure 75 t ha-1); 6) NM (N 120 kg ha-1,manure 75 t ha-1); 7) PM (P 26.2 kg ha-1, manure 75 t ha-1); 8) NPM (N 120, P 26.2 kg ha-1, manure 75 t ha-1);and 9) fallow (no fertilizer, no crop). N fertilizer was applied in the form of urea and P was applied as calcium super phosphate. The results showed that precipitation had a large effect on the response of wheat yield to fertilization. Manure (M), NP, PM, NM, and NPM treatments significantly increased (P < 0.05) average yield. In the NP, PM, NM and NPM treatments, the percentage increases in yield due to fertilization were highest in normal years, and lowest in the drought years. Long-term P application enhanced soil available P markedly, and manure applications contributed more to soil fertility than chemical fertilizers alone. Chemical fertilizers applied together with manure distinctly improved soil fertility.The results also showed that the soil nutrient concentration changed mainly in the 0-60 cm layers and fertilization and planting only slightly affected soil nutrients below the 100 cm layers.

  11. Effect of Polypropylene Fibers on the Long-term Tensile Strength of Concrete

    Institute of Scientific and Technical Information of China (English)

    YAO Wu; ZHONG Wenhui

    2007-01-01

    The influence of low volume fraction of polypropylene(PP) fibers on the tensile properties of normal and high strength concretes was studied. The experimental results indicate that the addition of PP fibers in concrete leads to a reduction in tensile strength during the age of 28 d. Whereas, after 28 days, there is a notable effect in tensile strength due to PP fibers restraining the formation and growth of microcracks in concrete, which improves the continuity and integrality of concrete structure. Thus, a low volume fraction of PP fibers is beneficial to enhancing the long-term tensile strength of concrete materials and improving the durability of concrete structures.

  12. Long-term Effect of TCM Decoctions in Treatment of Nephrotic Syndrome

    Institute of Scientific and Technical Information of China (English)

    魏连波; 叶任高; 栾图; 吕瑞和; 陈保田

    2002-01-01

    Fifty-seven cases of nephrotic syndrome were treated with TCM decoctions as accessory treatment for prednisone and cyclophosphamide, and the effects were observed in a follow-up period of 5-15 years. The long-term complete remission rate of 68.4% and recurrence rate of 26.3% in the treatment group were respectively higher and lower than those in the control group (P<0.01, and P<0.01). The results suggested that the TCM decoctions were very helpful in treating this condition.

  13. The effects of long-term administration of guarana on the cognition of normal, elderly volunteers

    Directory of Open Access Journals (Sweden)

    Jose Carlos Fernandes Galduróz

    Full Text Available Paulinia cupana (guarana is a Brazilian plant given great prestige in popular medicine, for example as being a potent stimulator of brain functions. The authors assessed the effects of the long-term administration of guarana on the cognition of normal, elderly volunteers. Forty-five volunteers were studied, with a random distribution in three experimental groups: placebo (n=15, caffeine (n=15, and guarana (n=15, in a double-blind study. There were no significant cognitive alterations in these volunteers.

  14. Acute and long-term effects from petroleum discharges on temperate and Arctic Calanus species

    OpenAIRE

    Jensen, Louise Kiel

    2011-01-01

    Papers 1 and 2 of this thesis are not available in Munin: 1. Jensen, L.K., Carroll, JL., Pedersen, G., Hylland, K., Dahle, S. and Bakke, T.: 'A multigeneration Calanus finmarchicus culturing system for use in long-term oil exposure experiments', Journal of Experimental Marine Biology and Ecology (2006) 333: 71-78. Available at http://dx.doi.org/10.1016/j.jembe.2005.12.001 2. Jensen, L.K. and Carroll, JL.: 'Effects of the volatile petroleum component xylene on Arctic algae and zooplankton' (su...

  15. Hurricanes vs. Humans: Their Comparative Long-Term Effects on Tropical Landscapes.

    Science.gov (United States)

    Lugo, A. E.

    2002-12-01

    Puerto Rico experiences about 50 hurricanes per century. These large-scale events last for hours, but have significant short, medium, and long-term effects on vegetation and landscape processes as shown in studies in the Long-Term Ecological Research program. Forest canopy characteristics, tree mortality rates, life history characteristics of both plants and animals, successional rates, landslide occurrence, and sediment erosion and transport are examples of ecological and landscape attributes that exhibit strong responses to hurricane frequency and intensity. However, Puerto Rico has also undergone dramatic land cover change due to human activity. The island as a whole has experienced a cycle of deforestation, agricultural use, land abandonment, forest recovery, and urbanization. These anthropogenic events leave a long-term legacy on both individual ecosystems and the landscape as a whole. Species composition, structure, and age of forests are significantly influenced by human activity, as are rates of sediment erosion and transport, and frequency and size of landslides. I will present comparative data on the effects of hurricanes and human activity on Puerto Rico's forests and landscape. I address the following questions: which of these two forces that jointly shape the island's biota and landscape has a greater influence on functioning at the ecosystem level and what are the management implications? It appears that human impact on sediment erosion and transport events is greater than that of hurricanes and that humans change species composition of forests more than do hurricanes. However, regardless of the nature of the new ecosystems formed due to human activity, these systems must cope with the forces (rain and winds) of hurricanes in order to persist on the landscape. Regardless of the power of hurricanes, they don't appear to reset the human legacy on the island's landscape.

  16. Post-effects of long-term water drougth in Mediterranean pine stands

    Directory of Open Access Journals (Sweden)

    Borghetti M

    2008-12-01

    Full Text Available Two studies were carried out on the effects of imposed water shortage in two Mediterranean pine stands growing in Southern Italy. The impact of a severe reduction in water availability on the growth of 50-year old Pinus halepensis trees (growing along the Ionian coast of Puglia, experiment 1 and 35-year-old Pinus laricio trees growing in Sila (Calabria Region, experiment 2 were studied. The experimental effects were followed for 12 months in experiment 1 and for 36 months in experiment 2, comparing covered plots and uncovered control plots. The experiment was carried out on plants of the same plots, to check if long-term water shortage caused post-effects on their growth. This research aimed to investigate what pines suffer during last years, considering the beginning of possible long-term effect on these pine forests. The results were different for the species. After treatment, the reduction of radial growth Pinus halepensis covered plants was observed, while a positive trend of growth of control trees was observed. A recovering of both covered and control Pinus laricio trees growth was observed.

  17. Long-term effects of prevention and treatment on youth antisocial behavior: A meta-analysis.

    Science.gov (United States)

    Sawyer, Aaron M; Borduin, Charles M; Dopp, Alex R

    2015-12-01

    Youth antisocial behavior exacts a tremendous toll on society and often persists into adulthood. Although researchers have identified a number of psychosocial interventions that prevent or reduce youth antisocial behavior in the short term, evidence of long-term intervention benefits has only recently become available. In addition, research on such interventions spans two substantial but largely separate bodies of literature: preventi